By Suleiman al-Khalidi
AMMAN (Reuters) - Syrian forces backed by tanks shelled parts of Deraa and stormed a mosque on Saturday, residents said, trying to quell resistance in the city at the heart of an uprising against President Bashar al-Assad.
Syrian troops and tanks first swept into Deraa on Monday to crush pro-democracy protests against Assad that have spread across the country of 20 million, posing the biggest challenge to his rule and prompting Western powers to impose sanctions.
A resident said Karak, a hilltop in Deraa's old quarter, bore the brunt of the shelling. Assad's brother, Maher, commands the Fourth Mechanised Division which stormed the city on Monday.
"The shelling has stopped. There are snipers on the roof of the mosque," he said, adding that forces appeared to be in control of the old quarter for the first time.
Residents said earlier they could hear heavy gunfire in the old city where the Omari Mosque, a focal point for protests, is located.
"It looks like they (security forces) want to finish their campaign today. From the new tank deployments, it looks as though they are intensifying their operations today," resident Abu Ahmad told Reuters by telephone earlier.
Deraa, a city near the border with Jordan with a population of 120,000, is the cradle of a six-week-old uprising which began with demands for more freedom and an end to corruption.
It developed into a movement to overthrow Assad following a violent state crackdown, in which a Syrian rights group said at least 500 people have been killed.
Despite the heavy military deployments and mass arrests, demonstrators again took to the streets calling for Assad's overthrow on Friday. His Baath Party has been in power in Syria since 1963, banning any opposition.
Soldiers in Deraa killed 19 people on Friday when they fired on protesters who were trying to enter the city from nearby villages in a show of solidarity, a medical source said. Syrian rights groups put Friday's death toll at 62.
The crackdown prompted Western powers to take their first concrete steps in punishing Syria for the bloodshed. Washington imposed new sanctions on government figures, including Assad's brother, Maher, and cousin, Atif Najib.
Ali Mamluk, director of general intelligence, was also targeted as was Iran's powerful Revolutionary Guard, accused of helping the Syrian crackdown, a charge Damascus denies.
European Union diplomats said they reached an initial deal to impose an arms embargo and would consider further measures.
"We will continue to work with our partners to ensure that those responsible for the violence are held personally to account," British Foreign Secretary William Hague said.
SYRIA BLAMES ARMED TERRORIST GROUPS
Demonstrations also flared on Friday in the central cities of Homs and Hama, Banias on the Mediterranean coast, Qamishly in the east, Harasta, a Damascus suburb, and the capital itself.
State news agency SANA said on Friday "armed terrorist groups" had killed soldiers near Deraa. It said groups had opened fire on the homes of soldiers in two towns near Deraa and were repelled by guards.
But a witness in Deraa said Syrian forces fired live rounds at thousands of villagers who descended on the besieged city.
A rights campaigner in Deraa said on Friday makeshift morgues in the city contained the bodies of 85 people he said had been killed since the army stormed the city on Monday. Residents say a humanitarian crisis is growing.
Western powers had sought for several years to engage Damascus and loosen its anti-Israel alliances with Iran and the militant groups Hezbollah and Hamas.
(Additional reporting by Khaled Yacoub Oweis in Amman; Writing by Yara Bayoumy in Beirut; Editing by Robert Woodward)