Elite forces loyal to Syrian President Bashar Assad pounded a rebel bastion in Homs on Thursday in what appeared to be a final push on the opposition stronghold after more than three weeks of siege and bombardment, activists said.
A senior official in the rebel Free Syrian Army told Reuters rebels in the district of Baba Amr were fending off more than 7,000 government troops. Opposition forces had promised to step up attacks elsewhere in Syria to try to relieve the pressure.
"Baba Amr will be the straw that will break the regime's back," Mohaimen al-Rumaid told Reuters from an area in Turkey near the Syrian border. "All of Syria is turning into Baba Amr."
Heavy shelling resumed overnight after several hours of sporadic bombardment, opposition sources in the city said.
'They're trying to finish it off'
They said rebels had repelled an attempt by government forces to advance into Baba Amr from the Hakoura area on its northern edge, but diplomats said earlier Syria's feared 4th Armored Division seemed determined to overrun the district.
Smugglers take 'path of death' to supply Syria revolt
"All the signs out of Homs are that they're trying to finish it off," a senior Western diplomat said.
The Obama administration summoned Syria's senior envoy in the U.S., Zuheir Jabbour, over the Homs offensive.
The State Department's top diplomat for the Mideast, Jeffrey Feltman, expressed his "outrage over the monthlong campaign of brutality and indiscriminate shelling" in Homs, according to a statement.
U.S. Secretary of State Hillary Rodham Clinton told members of Congress on Tuesday that Assad could be considered a war criminal.
Since the first week of February, government forces have showered parts of Homs with daily barrages of mortars, tank shells and rockets. The violence has caused many to flee the city of 1 million people, Syria's third-largest, while those who remain are trapped inside.
A motley band of army deserters and desperate insurgents who call themselves the Farouq Brigade of the Free Syrian Army have sworn to fight to the last man, one activist from Baba Amr told Reuters. Others, though, said some of the unit's leaders had already made their escape from the shattered neighbourhood.
Heavy artillery
Al-Rumaid admitted the rebels were far outgunned, armed with machine guns and mortars against armored forces backed by heavy artillery and rockets but said they were holding out.
Activists say hundreds of civilians have been killed in besieged opposition districts of Homs. Army snipers pick off civilians who venture out.
Reports from the city could not immediately be verified due to tight government restrictions on media work in Syria, where Assad is facing the gravest challenge of his 11-year rule.
Western and Arab governments, which have already called on Assad to step down and end the bloodshed, expressed mounting concern for the fate of civilians trapped in Homs.
The 4th Armored Division commanded by Maher Assad, the president's younger brother, has won a reputation for ruthlessness during the past year of revolt against the government.
The U.N. estimated that more than 7,500 people have been killed since the anti-Assad struggle started in March 2011, when protesters inspired by successful Arab Spring uprisings against dictators in Tunisia and Egypt took to the streets in Syria. As Assad's forces used deadly force to stop the unrest, protests spread and some Syrians took up arms against the regime.
Syria's government said in December that "armed terrorists" had killed more than 2,000 soldiers and police during the unrest.
A spokesman for the International Committee of the Red Cross, Hicham Hassan, said the violence in Homs was making the humanitarian situation more difficult.
"This makes it even more important for us to repeat our call for a halt in the fighting," he told Reuters in Geneva.
The ICRC said its Syrian Red Crescent affiliate had established 10 distribution and first aid points in Homs, but had been unable to operate in Baba Amr because of the violence.
Journalist escapes to Lebanon
Meanwhile, Spanish reporter Javier Espinosa, one of several Western journalists trapped in Baba Amr for a week, crossed to Lebanon on Wednesday, an activist said, following the escape on Tuesday of wounded British photographer Paul Conroy.
Thirteen Syrians were killed while aiding Conroy's escape, the activist group Avaaz said.
Still in Homs were French journalists William Daniels and Edith Bouvier, who was wounded in a Feb. 22 bombardment which killed veteran Sunday Times war correspondent Marie Colvin and French photographer Remi Ochlik. Their bodies remain there.
The Local Coordination Committees, a human rights monitoring group, said Bouvier refused to leave Baba Amr without the Syrians who were wounded by shelling while attempting to help her escape, and she has called on the French ambassador for help. The French Foreign Ministry demanded that the Syrian regime observe a cease-fire so Bouvier and Daniels could be evacuated.
The Associated Press and Reuters contributed to this report.
