Diego Azubel / EPA

A file photo dated Aug. 30 shows Chinese Vice President Xi Jinping at the Great Hall of the People in Beijing. Reports say Xi, who is expected to lead the ruling Communist Party from next month, is recovering from an injury.

Updated 12:45 p.m. ET Saturday: BEIJING - China's leader-in-waiting Xi Jinping appeared in public on Saturday for the first time in about two weeks, state news agency Xinhua reported, following rumors about his health or the state of the country's leadership succession.

Xinhua said Vice President Xi "arrived at China Agricultural University Saturday morning for activities marking this year's National Science Popularization Day."

Pictures on state television's main evening news showed a healthy-looking, relaxed Xi inspecting ears of corn, chatting with students and laughing with children. Reuters had reported that Xi was likely to make an appearance on Saturday.

A later, full description of Xi's visit by Xinhua said he inspected exhibitions on growing drought-resistant corn and a talk on how to fight food adulteration, a perennial problem in the world's second-largest economy.

"Food is the people's first necessity, and food safety is an important issue for people's livelihood," the report quoted him as saying.

None of the reports made mention of Xi's recent absence.

Sources have told Reuters Xi hurt his back while swimming earlier this month and that he had been obeying doctors' orders to get more bed rest and undergo physiotherapy.

Xi had been out of the public eye for almost two weeks and had skipped meetings with foreign leaders and dignitaries, including U.S. Secretary of State Hillary Clinton.

Chinese government officials repeatedly refused to say what happened to him, fuelling speculation that has included Xi supposedly suffering a heart attack, a stroke, emergency cancer surgery and even an attempted assassination.

The health of the country's leaders has long been considered a state secret in China.

The ruling Communist Party's refusal to comment on his disappearance from public view and absence from scheduled events was in keeping with its traditional silence on the question of the health of top leaders, but it had worried or mystified most China watchers.

Xi had last appeared in public on September 1. He pulled a back muscle while swimming shortly before Clinton arrived on an official visit on September 4, the sources said, forcing him to scrap a meeting with her the next day and also with Singapore Prime Minister Lee Hsien Loong.

On Wednesday, state media carried comments attributed to Xi for the first time since he dropped out of sight, but there was no public sighting of him or any new photographs.

Beijing has yet to announce formally a date for the party's five-yearly congress, at which Xi is tipped to replace Hu Jintao as party chief, although it is still expected to be held in mid or late October at the earliest.

In March next year, he is formally to take up the reins of the world's second-largest economy.

The uncertainty surrounding Xi's absence has had no impact so far on Chinese or foreign markets, which have been absorbed by Europe's debt crisis and China's own economic slowdown. But investors have been keeping a close eye on the mystery surrounding Xi, after months of high political drama in China.

Senior leader Bo Xilai was suspended from the party's 25-member Politburo in April and his wife convicted of the murder of a British businessman. Blind human rights activist Chen Guangcheng escaped from house arrest in April and took refuge in the U.S. embassy before leaving for New York.

In another scandal this month, a senior ally of President Hu was demoted after sources said the ally's son was killed in a crash involving a luxury sports car.

The trial of nine people charged in a case involving a teenager who sold his kidney to purchase an iPad and iPhone concluded in a Chinese court on Friday, according to state media.

The defendants included the surgeon who allegedly removed the kidney from the 17-year-old, identified only by his surname, Wang, and eight others who are accused of helping to plan and carry out the scheme.

The verdict would be announced at a later date, state-run Xinhua reported.

'Gambling debts'
Prosecutors in the Beihu District of Chenzhou, Hunan province, have accused defendant He Wei of arranging the transplant last year via Internet chat rooms. He was described by Xinhua as "penniless and frustrated over gambling debts."

Chinese man wakes up — minus his kidney

The doctor, Song Zhongyu, from a provincial hospital in Yunan province, allegedly transplanted Wang’s kidney to a recipient in April 2012, Xinhua said. Wang later suffered renal failure, the report said.

The defendant earned a little under $9,000 in the deal, Xinhua said. Another defendant, Su Kaizong, the contractor of the urology department of the hospital, earned around $9,500; Song, the surgeon, earned a little over $8,000; and other defendants involved in the scheme earned lesser amounts, Xinhua said.

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Wang, the young patient, was given around $3,500 upon leaving the hospital, according to the news service.

The incident came to light after Wang returned home and his mother demanded to know where he got the money to pay for an iPhone and iPad, Xinhua said. At that point, Wang confessed, Xinhua said.

Among the others arrested were two nurses, a surgical assistant and an anesthesiologist, Xinhua said.

China puts cops on trial for 'bending the law' to help wife of ousted politician

After the indictment was read in court on Thursday, Wang's attorney requested about $356,000 in compensation, the news agency said.

The British Broadcasting Corp. said the defendants face up to 10 years in prison if found guilty.

A first: More cheers than jeers at new Apple product debut in China

Huge popularity
Apple products are extremely popular in China, but their price tags tend to be too high for most workers to afford.

Products such as the iPhone and the iPad have quickly become must-have accessories for the country's youth and business elite in cities such as Beijing and Shanghai.

From 2011: Entire fake Apple shop found in China

Last year, the Cupertino, Calif., company's chief financial officer was quoted as saying that of all the Apple outlets in the world, the China stores clock on average the highest traffic and highest revenue.

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Reuters, file

Gu Kailai is the wife of China's former Chongqing Municipality Communist Party Secretary, Bo Xilai.

Updated at 12:25 p.m. ET: BEIJING -- The wife of ousted Chinese politician Bo Xilai and a family aide have been charged with the murder of a British businessman, the government said Thursday, pushing ahead a case at the center of a messy political scandal that exposed divisions in the country's leadership.

The official Xinhua News Agency reported that the prosecutor's indictment said Bo's wife, Gu Kailai, had a falling out with Briton Neil Heywood over money and worried that it would threaten her and their son's safety. Gu and the aide, Zhang Xiaojun, are alleged to have poisoned Heywood together, the report said. Heywood's death in November was attributed initially to a heart attack or excessive drinking.

"The facts of the two defendants' crime are clear, and the evidence is irrefutable and substantial. Therefore, the two defendants should be charged with intentional homicide," Xinhua said.

It did not give a date for the trial, but a family lawyer told Reuters it was likely to take place on August 7-8.

Thursday's brief report is the first official news that the case against Gu is proceeding since the announcement three months ago that she and Zhang were being investigated and that Bo was being suspended from the powerful Politburo for unspecified discipline violations. The Xinhua report did not mention Bo's case or a separate party investigation into Bo.

Prosecutors have interrogated Bo and Zhang and have "heard the opinions" of their defense lawyers, Xinhua said.

The scandal has exposed the bare-knuckled infighting that the secretive leadership prefers to hide and affirmed an already skeptical public's dim view about corrupt dealings in the party.

City divided by disgraced Communist leader's legacy

Disappeared from public view
Since Bo was dismissed in March, he and his wife Gu, formerly a powerful lawyer, have disappeared from public view and have not responded publicly to the accusations against them.

The charges were filed in the eastern city of Hefei, Xinhua said Thursday. It did not say when exactly the indictment was issued or when the crime occurred and why the case is being prosecuted in Hefei and not in Chongqing, the city Bo ran as Communist party secretary and where the couple lived.

But according to Si Weijiang, a prominent lawyer in China who is followed by 170,000 people on his microblog, Hefei, in eastern China's Anhui Province, was selected due to its political reliability.

Wang Shengjun, who is the chief justice of China's Supreme People’s Court, is from Anhui and the province has, according to Si, built a reputation of being politically reliable and harsh on defendants.

"The case being filed at Hefei, will set Chief Justice Wang's mind at ease," Si wrote Thursday.

Scandal sends China's netizens into a feeding frenzy

In another post, Si noted the intense political ramifications of this case.

"This is a political case. No accidents is success. So it [the court] must be a place that can be trusted," he wrote.

But Fang Hong, a Chongqing resident featured in a piece by NBC News in May, hailed the prosecution move as a "vindication of my criticism" of Bo's rule.

"They tried to destroy the rule of law so as to make it convenient for them to murder people, and now they will get what they deserve," he told NBC News.

"This case is being handled according to the law," he said, adding that "some people with limited understanding wrongly think it is a political striuggle, but it is not. ... What the law says is what they will get."

China.org.cn via Reuters, file

British businessman Neil Heywood, who died in November 2011, was a long-time friend of Bo Xilai and Gu Kailai.

Political ascent stopped
Thursday's announcement comes months before the ruling Communist Party unveils a new top leadership.

Before his ouster, Bo was one of China's most powerful and charismatic politicians. The son of a revolutionary veteran, Bo was seen as a leading candidate for a position in the Politburo Standing Committee, the highest ranks of power, when a younger group of leaders is installed later this year.

Son of sacked Chinese official fights back

On his rise, Bo led high-profile campaigns to bust organized crime and to promote communist culture. In doing so, however, his administration ran roughshod over civil liberties, angered some leaders and alienated others with his publicity seeking.

The removal of Bo has triggered rifts and uncertainty, disrupting the Communist Party's usually secretive and carefully choreographed process of settling on a new central leadership in the run up to its 18th congress.

Left-wing supporters of the charismatic Bo have defended him as the instigator of a much-needed new path for China, and many of them see him as the blameless victim of a plot.

Behind the Wall: Full NBC News coverage from China

The 18th Party Congress, scheduled to be held late this year, will appoint that leadership. President Hu Jintao and Premier Wen Jiabao will then step down from their government posts at the National People's Congress in early 2013, when Vice President Xi Jinping is likely to succeed Hu as president.

Growing credibility gap
Analysts here agree that the legal steps announced Thursday are part of the authorities' effort to dispose of the case and remove a major distraction before the once-in-a-decade leadership succession later this year.

However, this week has been a week of disruptions that have kept government propaganda officials and censors busy.

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Besides the ongoing saga of Bo, Beijing this past weekend dealt with the worst flooding in nearly six decades. Just as news of Gu’s charges came out, word also broke that the death count from the flooding, which previously had stood at 37, had been bumped up to at least 77. Many Beijing residents had been highly dubious of earlier government estimates of the death toll, highlighting the party's credibility gap.

The news also came on the eve of the 2012 Olympics in London, where China hopes again to top the tables in gold medals.

Still, the government was not taking any chances: the comments section on the official Weibo account of popular Chinese state newspaper, People's Daily, was turned off for the post regarding Gu's murder charges.

The Associated Press and Reuters contributed to this report.

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