Amman: Syrian security forces opened fire on mourners near a mosque in the flashpoint city of Deraa after a mass funeral for pro-democracy protesters, two witnesses said.
Security forces used live ammunition and tear gas to disperse thousands of people who were chanting freedom slogans after assembling near the old Omari mosque in the old quarter of the city, the witnesses said on Saturday.
Dozens of people have been killed in a wave of protests across Syria against the rule of President Bashar al-Assad.
A Syrian rights group said at least 37 people had been killed in protests across the country on Friday.
"Syrian security committed (in Deraa) what could be called a crime against humanity," the National Organisation for Human Rights said in a statement. "It fired indiscriminately on protesters and killed and wounded tens of them."
State television for its part said armed groups had killed 19 policemen and wounded 75 in the city, near the border with Jordan. The Interior Ministry warned it would not tolerate breaches of the law and would deal with "armed groups," state news agency SANA said.
United Nations Secretary General Ban Ki-moon told Assad in a telephone call "he was greatly disturbed by the latest reports of violence against protesters”, a UN statement said.
A witness in Deraa said he had seen at least four youths wounded by snipers being taken by protesters to a nearby clinic.
Residents say people avoid taking many of the wounded to state-run hospitals for fear the injured will be arrested by plain clothes security personnel stationed in hospitals.
Popular demonstrations calling for greater freedom, inspired by Arab uprisings that began in Tunisia and Egypt, have shaken Syria. Assad has responded with a mixture of force against protesters, gestures toward political reform and concessions to conservative Muslims, including closing Syria`s only casino.
In the early hours of Saturday, security forces used live ammunition to disperse hundreds of people in Latakia, causing scores of injuries and possible deaths, residents said.
One witness said he had seen water trucks washing blood off the streets near Takhasussieh School in the Sleibeh district.
"You can`t go two steps on the street without risking arrest," a resident said. "It`s difficult to know if there were deaths, but we heard heavy AK-47 fire."
Ban, who urged "maximum restraint" in a call with Assad a week earlier, told him on Saturday violence by any side was deplorable and the government had a duty to protect civilians.
There was no alternative to an immediate and inclusive debate on comprehensive reform, Ban said.
A key demand of the protesters is the repeal of emergency laws imposed by the Baath party after it took power in a coup in 1963 and banned all opposition.
Assad has ordered a committee to study replacing them with anti-terrorism legislation, but critics say it will probably grant the state many of the same powers.
On Friday, rallies swept Syria from Latakia in the west to Albu Kamal on the east, as demonstrations entered a fourth week. But on Saturday, most cities were calm.
Foreign Minister Walid al-Moualem told ambassadors in Damascus that "subversive elements infiltrated the protesters and opened fire on the police and the protesters to drag the country into violence and cause chaos”.
Assad, a member of the Alawite sect, which accounts for 10 percent of Syria`s population, has said the protests are serving a foreign conspiracy to sow sectarian strife.
The Interior Ministry accused "plotters pushed by known foreign sides" of firing at protesters to create a rift between people and police.
"(They) have infiltrated the ranks of the demonstrators to sow discord between the citizens and the security forces. There is no more room for leniency or tolerance in enforcing law ..."