A human rights activist said Syrian security forces killed at least 21 demonstrators on Friday as protests erupted throughout the country, including Damascus and its suburbs.
"Six confirmed dead in Hama and 15 in Homs so far," Ammar Qurabi, head of the National Organization for Human Rights in Syria, told Reuters by telephone from Egypt.
He also said residents in the coastal city of Banias feared the army, which they said was posted 4 km (2 miles) away, might storm the city.
A campaigner in Hama said "they [Syrian security forces] killed one protester when the demonstration began at the Orontes Square. Demonstrators re-assembled in al-Hader [old quarters] and another five fell there." The campaigner asked not to be identified.
Four additional protesters were killed in the oil city Deir al-Zor, according to a local tribal leader. These were the first deaths to be reported in the oil-rich town, one of Syria's main oil producers.The tribal leader added that thousands of angry residents gathered to protest at nightfall.
Syrian state TV reported that an army officer and four policemen were shot dead by a "criminal gang" in Homs that same day.
Witnesses said security forces also opened fire at protesters in the town of Tel, just north of the capital, wounding demonstrators.
Also on Friday, Syrian security forces arrested opposition leader Riad Seif at a pro-democracy demonstration in the Midan district of Damascus, according to his daughter and human rights campaigners.
"My father was shoved into a bus with other protesters who were detained during the demonstration near the al-Hassan mosque," Jumana Seif told Reuters.
Human rights campaigners say army, security forces and gunmen loyal to President Bashar Assad had killed at least 560 civilians during pro-democracy demonstrations that started in March.
Thousands have been arrested and beaten, including the elderly, women and children, they said.
Officials give a much lower death toll and say half the fatalities have been soldiers and police, and blame "armed terrorist groups" for the violence.
Western powers, which had sought for several years to engage Damascus and loosen its anti-Israel alliances with Iran and the militant groups Hezbollah and Hamas, condemned the bloodshed.
The United States, which called the army crackdown in Daraa "barbaric", imposed further targeted sanctions last week against Syrian officials and Europe's main powers have been pushing for similar European Union measures.
Last week, Assad ordered the army into Daraa, cradle of the uprising that began with demands for greater freedom and an end to corruption and is now pressing for his removal.
An ultra-loyalist division led by his brother Maher shelled and machinegunned Deraa's old quarter on Saturday, residents said. Syrian authorities said on Thursday the army had begun to leave Daraa, but residents described a city still under siege.
Aid workers from the Red Cross and Red Crescent delivered their first emergency relief supplies to Daraa on Thursday, bringing drinking water, food and first aid materials. They had no immediate information on casualties in the city.
Human Rights Watch cited figures from Syrian rights groups saying 350 people had been killed in Daraa. It urged authorities on Friday to "lift the siege" on the city and to halt what it called a nationwide campaign of arbitrary arrests.
"Syria's authorities think that they can beat and kill their way out of the crisis," said HRW Middle East director Sarah Leah Whitson. "But with every illegal arrest, every killing of a
protester, they are precipitating a larger crisis."
Diplomats said the European Union could reach a preliminary agreement on imposing sanctions on Syria's ruling hierarchy on Friday, but had yet to decide whether Assad should be included.
Assad has said the protesters were part of a foreign conspiracy to cause sectarian strife.
His father Hafez Assad used similar language when he crushed Islamist and secular challenges to his rule in the 1980s, culminating in the violent suppression of an uprising in the city of Hama in which 30,000 people were killed.
Hafez lost two wars to Israel, as defense minister in 1967 and as president in 1973. He maintained Syria's position as a central player in Middle East geopolitics by building ties with Shi'ite Iran and backing Palestinian guerrilla forces.
The younger Assad, who belongs to the minority Alawite sect, has reinforced the anti-Israeli alliance with Tehran, despite disquiet on the part of Syria's majority Sunni population.
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