Syria blocked a Red Cross convoy Friday from delivering badly needed food, medical supplies and blankets to a rebellious neighbourhood of Homs cut off by a month-long siege.
Activists accused regime troops who overran the shattered district of execution-style killings and a scorched-earth campaign.
Humanitarian conditions in the former rebel stronghold of Baba Amr have been described as catastrophic, with extended power outages, shortages of food and water, and no medical care for the sick and wounded.
British Prime Minister David Cameron called Homs "a scene of medieval barbarity."
Syrian state TV showed burned-out and destroyed buildings in Baba Amr, a western neighborhood of Homs, which was covered with a blanket of fresh snow.
Syrian government forces took control of Baba Amr on Thursday after rebels fled the district under constant bombardment that activists said killed hundreds of people since early February. The Syrian regime has said it was fighting "armed gangs" in Baba Amr, and had vowed to "cleanse" the neighbourhood.
"It is unacceptable that people who have been in need of emergency assistance for weeks have still not received any help," said Jakob Kellenberger, president of the International Committee of the Red Cross.
'The images which we have seen in Syria are atrocious. It's totally unacceptable, intolerable. How, as a human being, can you bear this situation?' —U.N. Secretary-General Ban Ki-moon
The Red Cross said it had received permission from the government of President Bashar Assad on Thursday to enter Baba Amr, on the western side of Homs, and a convoy of seven trucks with 15 tons of humanitarian aid was poised to do so, but authorities then blocked their access. There was no explanation from the government about the change.
"We are staying in Homs tonight in the hope of entering Baba Amr in the very near future," Kellenberger said.
U.N. Secretary-General Ban Ki-moon called on Syria to give humanitarian workers immediate access to people who desperately need aid.
"The images which we have seen in Syria are atrocious," said Ban. "It's totally unacceptable, intolerable. How, as a human being, can you bear this situation?"
Regime forces burning houses, activists say
Meanwhile, activists say that regime troops were burning houses and going street by street in a scorched-earth campaign against rebels fighting to oust President Bashar Assad, the news agency reported. The claims could not be independently verified, as information from Baba Amr has been difficult to obtain in recent days.
Sami Ibrahim, an opposition activist, told CBC News that the regime is targeting the remaining buildings that have not been destroyed.
"Now the tanks start shelling the houses," he said. "This kind of huge punishment against the people of Baba Amr. Now, no communication at all, and all no electricity."
France said Friday it will close its embassy in Syria, a day after two French journalists escaped to Lebanon after being trapped for days in Homs.
French President Nicolas Sarkozy made the announcement in Brussels, where EU leaders were debating their response to the Syrian military's crackdown on the opposition uprising.
The United States and Britain already have closed their embassies in Syria.
"We have decided to close our embassy," Sarkozy told reporters in Brussels. "What is happening is a scandal."
Two French journalists escape to France
Photographer Daniel Williams and Edith Bouvier, a reporter for the daily Le Figaro who suffered leg fractures in an attack that killed two colleagues, escaped to Lebanon on Thursday. The two French journalists flew out of Lebanon to France on Friday, two Lebanese airport officials confirmed. The officials spoke on condition of anonymity because they were not authorized to speak to the media.
French president Nicolas Sarkozy greeted them on their arrival Friday at the military airport of Villacoublay west of Paris.
The Syrian army's victory over the main rebel stronghold Thursday set the stage for the military to turn its attention and firepower to other insurgent areas farther north, the New York Times reported.
Activist groups said protesters took to the streets in towns across the country on Friday, many of them meeting with tear gas, gunfire and arrest campaigns by Syrian security forces.
With government forces moving in, the UN human rights office expressed concern over reports suggesting former rebel areas were being subjected to bloody reprisals, Reuters reported.
"We are alarmed at reports starting to come out of the Baba Amr district of Homs after it was taken over by government forces …," UN human rights spokesman Rupert Colville told a news briefing in Geneva.
"Although we are not, at this point, in a position to confirm any of those reports, we would like to remind the authorities of their responsibilities under international law."
Homs battle zones
Mouse over the red circles to learn more about each neighbourhood.
Source: Wire reports and CBC News stories. Base map: Google