Syrian President Bashar al-Assad's forces bombarded opposition Sunni Muslim districts in the city of Homs for the 20th day on Thursday, activists said, despite international outrage over the reported killing of more than 80 people on Wednesday.
Rockets, artillery and mortar rounds rained on the districts of Inshaat and Baba Amro, where Free Syrian Army rebels appear to be holding their ground under heavy fire. In the Khalidiya district mosques called on inhabitants to take cover as mortar rounds started falling on the area.
Explosions are shaking the whole of Homs. God have mercy, Abdallah al-Hadi said from the city.
Two Western journalists were among those killed on Wednesday in an intensification of the offensive to crush resistance in Homs, one of the focal points of a nationwide uprising against Assad's rule.
French President Nicolas Sarkozy described the deaths of the two journalists, French photographer Remi Ochlik and American Marie Colvin of Britain's Sunday Times, as an assassination, and said the Assad era had to end.
That's enough now, Sarkozy said. This regime must go and there is no reason that Syrians don't have the right to live their lives and choose their destiny freely. If journalists were not there, the massacres would be a lot worse.
France and Britain demanded that three other Western journalists wounded in the strike on a house in Homs be given urgent medical care.
In the United States, Republican presidential candidates Mitt Romney and Newt Gingrich supported the idea of arming the Syrian opposition.
Romney said the United States needed to team up with allies to help the rebels. We need to work with Saudi Arabia and with Turkey to say, 'You guys provide the kind of weaponry that's needed to help the rebels inside Syria,' he said.
The White House, which so far has been against military intervention in Syria, has hinted that if a political solution were impossible it might have to consider other options.
More than 60 bodies, both rebel fighters and civilians, were recovered on Wednesday from one area of Baba Amro, a Sunni Muslim district of Homs opposed to Syria's Alawite rulers, after an afternoon bombardment on Wednesday. Some 21 were killed earlier in the day, activists said.
Helicopters flew reconnaissance overhead then the bombardment started, Homs activist Abu Adi told Reuters.
Videos uploaded by opposition activists showed smashed buildings, deserted streets, and doctors treating wounded civilians in primitive conditions in Baba Amro, the main target of Assad's wrath.
The worsening humanitarian situation in Homs and other embattled towns will dominate Friends of Syria talks in Tunis on Friday involving the United States, European and Arab countries, Syria's neighbour Turkey and other nations clamouring for Assad to halt the violence and relinquish power.
The two journalists were killed when the house in which they were staying after sneaking over the Lebanese border into Homs was hit by rockets. Sunday Times editor John Witherow said Colvin, a veteran war reporter, and her colleagues may have been deliberately targeted.
They certainly knew that she was there from her reports and broadcasting. And the question is, could they use technology or other means to identify exactly where she and some other journalists were hiding? Witherow said on BBC television.
It seems to me perfectly reasonable to assume that they would have targeted them.
The last dispatch from Colvin - who wore a trademark black eye-patch since being wounded in Sri Lanka in 2001 - described the misery inside Baba Amro.
Women and children were crammed together into a basement, huddled in fear and a two-year-old child had died in front of her, she reported on British radio.
British photographer Paul Conroy, reporter Edith Bouvier for French newspaper Le Figaro and Paris-based photographer William Daniels were also wounded in the strike on the Homs house, which global advocacy group Avaaz said had been occupied by journalists and opposition activists.
French Foreign Minister Alain Juppe said a Syrian army ceasefire to give rapid access to humanitarian aid was imperative, adding that the response by the Syrian government to the wounding of Bouvier was insufficient.
Britain's Foreign Office summoned Syria's ambassador and demanded that Conroy receive medical treatment.
Several hundred people have been killed in Homs in daily bombardments by the besieging forces using artillery, rockets, sniper fire and Soviet-built T-72 tanks.
Residents fear Assad will subject the city to the same treatment his late father Hafez inflicted on the rebellious town of Hama 30 years ago, when at least 10,000 were killed.
The army is blocking medical supplies and electricity is cut off 15 hours a day, activists say. Hospitals, schools and shops are shut and government offices have also closed.
In an effort to bring relief to hungry and bloodied civilians in Homs, the International Committee of the Red Cross was in talks with the Syrian government and opposition figures to seek agreement on a daily two-hour cessation of hostilities.
U.N. humanitarian chief Valerie Amos will head to Syria soon in an attempt to secure access for aid workers.
Assad has called a referendum on a new constitution on Sunday, to be followed by a multi-party parliamentary election, which he says is a response to calls for reform. The plan is supported by his allies Russia and China but Western powers have dismissed it and the Syrian opposition has called for a boycott.
Although some say support around Assad is crumbling, others say he could hang on for many months more if he is ever to join Libya's Muammar Gaddafi, Egypt's Hosni Mubarak, Tunisia's Zine al-Abidine Ben Ali and Yemen's Ali Abdullah Saleh on the list of leaders deposed in the Arab Spring.
There are also fears the revolt could flare into a religion-based civil war and spread across the volatile Middle East.
(Additional reporting by Erika Solomon and Mariam Karouny in Beirut, John Irish in Paris; Steve Gutterman in Moscow, Stephanie Nebehay in Geneva, Peter Griffiths in London; Editing by Rosalind Russell and Alessandra Rizzo)