DAMASCUS (AFP) – Anti-government demonstrations across Syria saw 24 protesters killed in clashes with security forces as thousands marched for change, the head of the National Organisation for Human Rights said.

Residents in the southern city of Daraa, which has become a focal point for opponents of the regime, reported that demonstrators had been fired on, sprayed with tear gas and targeted by other violent crowd control tactics.

“We have the names of 19 demonstrators killed in Daraa, and we have been told of the deaths of two protesters in Homs and three in Harasta,” Ammar Qurabi told AFP by telephone from Cairo, where he lives in exile.

“We are aware that live bullets, tear gas and another gas that causes fainting were used,” he added.

Earlier, other activists said 13 protesters had been killed in Daraa, a number of people wounded in the central industrial city of Homs and also spoke of fighting in Harasta, a Damascus suburb.

President Bashar al-Assad, under pressure to introduce major political reforms and end emergency powers which give security services great leeway to crush dissent, had ordered a probe into previous protest casualties in Daraa.

The official SANA news agency said 19 members of the security forces were killed and 75 were wounded by “armed groups” in Daraa.

US President Barack Obama condemned what he called an “abhorrent” crackdown on the demonstrators and also hit out at violence committed by protesters.

“I strongly condemn the abhorrent violence committed against peaceful protesters by the Syrian government today and over the past few weeks,” Obama said in a written statement, the latest in a flurry of US rebukes of Damascus.

“I also condemn any use of violence by protesters. I call upon the Syrian authorities to refrain from any further violence against peaceful protesters.”

The interior ministry said Syrian authorities will face up to armed groups firing indiscriminately on demonstrators and security forces.

“We will not allow confusion between peaceful demonstrations and (acts of) sabotage (aimed at) sowing discord, harming national unity and destabilising the foundations of Syrian policy,” said a statement published early Saturday by SANA.

The statement spoke of “plotters… pushed by known foreign parties who reject the reforms and turn up their noses at the popular demands.”

“These people have infiltrated the ranks of the demonstrators and fired indiscriminately to sow discord between the citizens and the security forces. They have set fire to public institutions, attacked soldiers and security agents who refrained from opening fire, which caused a large number of dead and wounded among them,” the statement said.

State television said “saboteurs and conspirators opened fire on residents and security forces” alike in Daraa, killing two people — an officer and an ambulance man.

State television broadcast footage showing young men in keffiyehs standing behind trees while the sound of automatic weapons fire could be heard.

The agricultural city of Daraa has been the centre of anti-government protests marred by deadly violence that human rights activists blame on the security services and the government blames on “armed” groups.

In Homs, meanwhile, SANA said “hundreds of people had been wounded.” Among them, it said, six members of the security forces were hospitalised, one of them in critical condition.

“Masked men on motorcycles fired indiscriminately on citizens, and armed groups set fire to police cars and fired at police and security agents,” it said.

Abdel Karim Rihawi, who heads the Syrian League for the Defence of Human rights, said several people were injured in clashes in Homs and that there had also been fighting in Harasta.

Rihawi also said several thousand people demonstrated in the port city of Banias and Tal, 20 kilometres north of Damascus.

SANA also spoke of demonstrations in Latakia, Banias and Qamishli, which it said were peaceful.

Thousands also marched in five towns in northern Syria, mainly in predominantly Kurdish Hassake and Ammuda, calling for an end to emergency rule and the release of prisoners, another rights activist said.

“More than 3,000 people, Kurds, Arabs and Assyrians (Christians), demonstrated in Qamishli after Friday prayers before staging a sit-in on the main road,” Kurdish rights activist Radif Mustafa told AFP.

The rallies came a day after Assad granted citizenship to tens of thousands of Kurds who had been denied nationality for nearly half a century because of a controversial census.

Until Friday, Syrian rights activists estimated that more than 130 people had been killed in clashes with security forces, mainly in Daraa and Latakia, since the start of political unrest on March 15.

Amnesty put the latest overall figure at at least 171 people.