U.S. officials are denouncing Syria for the killings of two foreign journalists, including American Marie Colvin, but the condemnations haven't stopped Syrian forces from carrying out new attacks on opposition strongholds.
Syrian President Bashar Assad's military sent tanks into the rebel district of Baba Amr in the an opposition stronghold of Homs on Thursday after 20 days of sustained bombardment, opposition sources told Reuters.
"Tanks have entered the Jobar area in the south of Baba Amr," activist Abu Imad told Reuters from the city.
Government forces also resumed shelling the neighborhood, where hundreds have died in a weeks-long siege.
About 30 people, including two Western journalists, were killed in shelling on Wednesday — most of them in Baba Amr, which is the center of the resistance in the city.
Homs-based activist Omar Shaker said intense barrages hit residential districts in Baba Amr again Thursday, but there was no immediate word on casualties. He said food, water and medical supplies are running dangerously low in Baba Amr.
Two journalists killed in Homs shelling. Marie Colvin an American born war reporter for the Sunday Times of London and French photographer, Remi Ochlik - have been killed in Syria. They died during the latest bombardment of Homs. ITN's Tim Ewart has a clip from one of Colvin's last reports.
"Every minute counts. People will soon start to collapse from lack of sleep and shortages in food," he said.
On Wednesday, shelling of Baba Amr killed American-born veteran war correspondent Marie Colvin and French photographer Remi Ochlik.
NBC's Richard Engel reports on the tense situation in Syria where an American reporter and French photojournalist were recently killed.
They were among a group of journalists who had crossed into Syria illegally and were sharing accommodations with activists, raising speculation that government forces targeted the makeshift media center where they were staying. But opposition groups had previously described the shelling as indiscriminate. At least two other Western journalists were wounded on Wednesday.
A Syrian Foreign Ministry spokesman offered condolences to the families of Colvin and Ochlik but rejected any responsibility for their deaths. The spokesman urged foreign journalists to respect Syrian laws and not to sneak into the country.
Britain's Foreign Secretary William Hague said nations were considering action against Syria in meetings on the sidelines of an international conference in London. Hague said he would discuss "what we can achieve" with U.S. Secretary of State Hillary Rodham Clinton and many of the Arab League leaders.
Officials say Britain, the United States, Turkey, Qatar and others plan talks on the margins of a conference on Somalia.
Meanwhile, a panel of U.N. human rights experts said Thursday that the United Nations has a secret list of top Syrian officials who could face investigation for crimes against humanity carried out by security forces.
The U.N. experts indicated that the list goes as high as President Bashar Assad.
Thousands of Syrians have died in the violence since March and the panel, citing what it called a reliable source, said at least 500 children are among the dead.
"A reliable body of evidence exists that, consistent with other verified circumstances, provides reasonable grounds to believe that particular individuals, including commanding officers and officials at the highest levels of government, bear responsibility for crimes against humanity and other gross human rights violations," said the report by the U.N.-appointed Independent International Commission of Inquiry on Syria.
"The commission has deposited with the United Nations High Commissioner for Human Rights a sealed envelope containing the names of these people, which might assist future credible investigations by competent authorities."
It doesn't say who these investigating authorities might be, but the U.N.'s top human rights official has previously called for Syria to be referred to the International Criminal Court in The Hague. Members of the 47-nation U.N. Human Rights Council are expected to hold a special meeting on Syria in Geneva next week, at which the panel's report will be formally presented.
Systematic killing of civilians
The U.N. panel was denied entry to Syria by the government, which accused it of ignoring official information and exceeding its mandate. The panel instead gathered much of its information from sources outside the country, including human rights activists and Syrian army defectors.
The report claims that the ruling Baath Party's National Security Bureau was responsible for translating government policies into military operations that led to the systematic arrest or killing of civilians.
It says the four main intelligence and security agencies reporting directly to Assad — Military Intelligence, Air Force Intelligence, the General Intelligence Directorate and the Political Security Directorate — "were at the heart of almost all operations."
The report details how businessmen helped hire and arm informal pro-government militias known as the Shabbiha.
"In a number of operations, the commission documented how Shabbiha members were strategically employed to commit crimes against humanity and other gross violations," it said.
The report also identifies 38 detention centers "for which the commission documented cases of torture and ill-treatment since March 2011."
Armed opposition groups, loosely connected under the umbrella of the Free Syrian Army, also committed some gross human rights abuses, the panel said. It cited the torture and execution of soldiers or suspected pro-government militia members.
But such actions were "not comparable in scale and organization with those carried out by the state," it added.
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The Associated Press and Reuters contributed to this report.