Manan Vatsyayana / AFP - Getty Images

Indian private security guards man the entrance to the Lok Nayak hospital in New Delhi on May 15, 2013. A defendant on trial over a fatal gang-rape in New Delhi last December is critically ill after being attacked in prison, his lawyer said Wednesday, weeks after the main accused died in the same jail.

One of the men on trial for the fatal gang rape of a student on a bus in India has been beaten and poisoned by prison inmates and is unconscious in the hospital, his lawyer said on Wednesday.

Prison authorities denied any mistreatment of Vinay Sharma, who has been at New Delhi's Tihar Jail since he was arrested on suspicion of attacking a woman in December. The attack stunned India and brought thousands of protesters onto the streets.

One of Sharma's co-accused, Ram Singh, the alleged ringleader, was found hanged from a ceiling grill inside his cell in March. Police described his death as suicide although a judicial inquiry is pending.

Sharma's lawyer, A.P. Singh, accused inmates of "beating him on the chest" and poisoning his food, and said he was admitted to Lok Nayak Jai Prakash Hospital on Tuesday after being treated at another city hospital since Sunday.

"Vinay was beaten by four or five fellow inmates inside the jail premises," he told Reuters, adding he was in an unconscious state.

Sunil Gupta, a spokesman for Tihar Jail, said Sharma was being treated in a city hospital for a fever.

"There was no such beating of Vinay to my knowledge. All the allegations are false," he said.

Police arrested Sharma and Singh, along with three other adult men and a teenage boy, on charges of raping the 23-year-old physiotherapy student on a moving bus and fiercely beating her and her male friend on Dec. 16.

The woman died of her injuries in a Singapore hospital two weeks after the assault, which enraged Indians, who protested in the thousands for days to demand better law enforcement to fight gender crimes.

The city court where Sharma has stood trial since early this year asked jail authorities and doctors on Wednesday to file reports on his health on Thursday.

Sharma was falsely implicated in the case, his lawyer said at the start of the trial.

Raveendran / AFP - Getty Images file

Delhi Metro passengers watch a policeman as he patrols with a sniffer dog on a train in this file photo.

Passengers on Delhi's subway face being breath-tested for alcohol consumption in an experiment aimed at preventing late-night brawls, according to local media reports.

Anyone who appears drunk will be tested and possibly refused entry to the metro system, according to the Hindustan Times.

The pilot project seeks to reduce the number of late-night fights on the city’s subway, which carries almost 2 million people a day.

It also follows wider public concern about alcohol and lawlessness. The alleged perpetrators of the December 16, 2012 gang rape on a New Delhi minibus - in which a medical student died, prompting global outrage – were drunk, according to prosecutors.

Although there is no law against being drunk on a train in India, anyone found to have more than 30mg of alcohol per 100ml of blood will be denied travel, according to the Telegraph newspaper in Calcutta.

"Drunkenness is an unnecessary nuisance to other passengers. It's uncomfortable if you have to share space with someone who is reeking of alcohol," Hemendra Singh, spokesman for the Central Industrial Security Force (CISF), which is responsible for metro security, told AFP.

Singh said officers would only breath-test people who shows signs of being under the influence of alcohol, adding that drunken brawls had become a problem on the metro, especially in the late evening.

The CISF has asked metro authorities for 130 hand-held breath-testing devices, similar to the ones used by traffic police.

Not everyone has welcomed the idea. “Not everyone who drinks is a potential rapist or a molester to be kept under watch. If there was a measure for silliness, this beats all records,” 21-year-old student Rakesh Srivastava told the Calcutta Telegraph. 

Related:

• Female tourists shun India after gang rape, murder
• 5 accused men plead not guilty in India gang rape
• India gang-rape victim's father: Hang the 'monsters' responsible

The number of female tourists visiting India has fallen by more than a third since the gang-rape in which a 23-year-old student died, according to business leaders there.

Visitor numbers have dropped in all parts of the country, not just in New Delhi, where December’s attack took place, the Associated Chambers of Commerce and Industry of India (Assocham) said Monday.

The brutal assault was shocking even to a nation inured to sexual crimes against women, and thousands of protesters took to the streets in the weeks that followed to demand tougher action.

Four days later, a British woman in Agra jumped from a second-floor hotel room when she feared the manager was trying to break in, while in another case a Swiss man was held at gunpoint while his wife was gang-raped in Madhya Pradesh.

 “From December 2012 onwards the inflows of women foreign tourists to the country have gone down by 35 percent and the overall tourism being affected by 25 percent,” said Assocham’s secretary general, DS Rawat, in a press release.

Tour operators have reported that canceled bookings -- “especially from women” -- were mostly from the U.S., Britain, Canada and Australia, Rawat said.

He said the string of high-profile sex crimes “raised concerns about the safety of female travelers to the country,” adding that the cases attracted “international attention.”

He called on his country to strengthen security at major tourist spots, warning that India’s unsavory reputation could inflict “long-term” damage on its $17 billion annual tourism revenues.

About 6.6 million international tourists visited India last year, India’s tourism ministry estimates.

In the Dec. 16 attack, police say the gang lured the 23-year-old victim onto a bus in New Delhi, where they repeatedly raped and assaulted her with a metal bar before throwing her bleeding onto a highway. She died of internal injuries two weeks later.

Related:

5 accused men plead not guilty in India gang rape

India gang-rape victim's father: Hang the 'monsters' responsible

Authorities: Alleged ringleader in India gang rape hangs himself

Adnan Abidi / Reuters

Women hold placards as they join others in a march past a metro station undergoing construction during a rally organized by Delhi's chief minister protesting for justice and security for women, in New Delhi on Jan. 2. The ashes of the Indian student who died after being gang-raped were scattered in the Ganges river on Tuesday as reports of more attacks stoked a growing national debate on violence against women. The death of the 23-year-old woman, who has not been named, prompted street protests across India, international outrage and promises from the government of tougher punishments for offenders.

Marchers protested in New Delhi on Wednesday as the horrific gang rape and murder of a student continued to reverberate across India. The 23 year old victim's family said that they would not rest until her killers are hanged. Police are finalizing their investigation before charges are laid against the suspects this week. The ruling Congress party reportedly pushed for tougher punishments for sex crimes, including chemical castration, and authorities in New Delhi launched a hotline to improve safety for women in a city dubbed "India's rape capital."

-- Agence France-Presse

Dar Yasin / AP

Delhi's chief minister, center, and others offer prayers for a gang rape victim, at Mahatma Gandhi memorial, in New Delhi, India, Jan. 2.

Raveendran / AFP - Getty Images

Indian protesters shout anti-government slogans during a protest against rape in New Delhi on Jan. 2. The family of an Indian gang rape victim said that they would not rest until her killers are hanged as police finalized their investigation before charges are laid against the suspects this week. The ruling Congress party reportedly pushed for tougher punishments for sex crimes, including chemical castration, and authorities in New Delhi launched a hotline to improve safety for women in a city dubbed "India's rape capital."

Anindito Mukherjee / EPA

A child carries placards that contain pro-women slogans at the Mahatma Gandhi memorial, Rajghat, during a peace prayer meeting in New Delhi, India, on Jan. 2. The event was organized by the Delhi Government, Delhi Commission for Women to pay homage to the 23 year old Delhi gang rape victim and for women safety.

Dar Yasin / AP

Female Indian paramilitary soldiers watch as Indian women march to mourn the death of a gang rape victim in New Delhi, India, on Jan. 2. India's top court said it will decide whether to suspend lawmakers facing sexual assault charges as thousands of women gathered at the memorial to independence leader Mohandas K. Gandhi to demand stronger protection for their safety.

Previously on PhotoBlog:

• Police try to temper outrage over gang rape
• Protesters clash with police in India over gang rape of medical student
• Tear gas used to quell India gang-rape protests
• Fury, anguish after hours-long gang-rape in India

Mansi Thapliyal / Reuters

Mahesh Chaturvedi, 63, reads a copy of the Bhagavad-Gita, one of Hinduism's most holy books, on a metro train in New Delhi on October 2, 2012.

63-year-old Mahesh Chaturvedi says that the soul of Mahatma Gandhi resides in him and he has been sent to continue the work of the man known by many Indians as the Father of the Nation, Reuters reports.

See more Gandhi-related images on PhotoBlog

Since his self-proclaimed transformation into Gandhi in 2002, Chaturvedi has traveled extensively, playing up to his resemblance to Gandhi at protests and demonstrations.

Mansi Thapliyal / Reuters

Mahesh Chaturvedi poses for a photo in front of a statue of Gandhi in the old quarters of New Delhi on October 25, 2012.

Mansi Thapliyal / Reuters

Mahesh Chaturvedi (front center) talks on the phone on September 28, 2012.

Mansi Thapliyal / Reuters

A man takes a photo as Mahesh Chaturvedi (back to camera), walks on the streets of New Delhi on September 28, 2012.

Kevin Frayer / AP

A barber gives a Hindu boy his first haircut before going for a holy dip in the Yamuna river on Sharad Purnima, an auspicious day for the new moon in the fall, in New Delhi, India on Oct. 29, 2012.

Kevin Frayer / AP

A boatman feeds birds on the Yamuna River in New Delhi on Oct. 29, 2012.

Kevin Frayer / AP

A barber gives Hindu boy Vanshu, 5 months, his first haircut as he is held by father Amit, second right, as his mother Rakhi Bansal, right, looks on before a holy dip in the Yamuna River on Oct. 29, 2012.

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