Beirut: Human rights activists say Syrian secret police have arrested opposition leader Riad Seif, at a demonstration in central Damascus, his daughter and human rights campaigners said.

"My father was shoved into a bus with other protesters who were detained during the demonstration near the Al Hassan mosque," Jumana Seif said.

The news followed reports that thousands of Kurds are demonstrating in Eastern Syria demanding political freedom while maintaining national unity, a senior Kurd source said.

Witnesses said that dozens of Syrian protesters ran through streets of the Damascus district of Midan after midday prayers on Friday calling for the overthrow of President Bashar Al Assad.

Broken up

They said the protest was broken up within minutes by plain-clothed security forces. Al Jazeera television showed footage of people marching and then running, shouting for "the overthrow of the regime".

The news came as witnesses reported Syrian tanks deploying inside the city of Homs, and that security forces were firing at a protest taking place in the town of Tel, north of Damascus.

Protesters were being injured, the witness said.

President Bashar Al Assad's troops have deployed in force in the Mediterranean protest hub of Banias and the other hotbeds of Ar-Rastan and Homs, activists said, after they pulled out of the restive town of Daraa in the south following a 10-day lockdown.

Hundreds of troops withdrew from Daraa on Thursday, and the military said the operation carried on overnight into Friday.

"Throughout the night, they withdrew from Daraa and this is continuing today. The troops' departure is gradual," General Riad Haddad, the military's political department chief, told AFP.

The army had rolled into the town on April 25 to quell the demonstrations that began three days after the unprecedented protest movement was born in Damascus on March 15.

Haddad said 600 people were arrested in Daraa during the 10-day operation.

On Wednesday, an activist had said around 100 tanks and troop transports converged on Ar-Rastan, near the central city of Homs.

Syrian security forces took strict measures around the country as anti-regime protesters prepared for a new day of demonstrations Friday, activists said.

The activists said security forces set up checkpoints and closed some areas that experienced protests in recent weeks.

More than 565 civilians killed

More than 565 civilians and 100 soldiers have been killed since an anti-regime uprising, inspired by revolts in Tunisia and Egypt, began in mid March, according to rights groups.

In the Damascus suburb of Douma, scene of intense protests over recent weeks, security forces cordoned off the area to prevent anyone from entering or leaving, a witness said.

15 tanks

A witness near Douma said he saw a train carrying about 15 army tanks heading north Thursday evening toward the central province of Homs, another site of recent violence.

In the coastal town of Banias, a resident said the area was calm but under the siege of army units ahead of a planned demonstration after the Friday prayers.

In the southern city of Daraa, where the army announced the end to an 11-day military operation Thursday, residents said troops were still in the streets, causing some would-be demonstrators to be wary of taking part in a planned protest Friday.

Earlier, security forces moved into central Syria and coastal areas ahead of Friday prayers in a test of will for demonstrators determined to maintain protests against the rule of President Bashar Al Assad.

In a show of force, tanks had  taken up positions near the urban centres of Homs, Rastan and Banias in the past two days.

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.

Old quarter machine-gunned

An ultra-loyalist division led by his brother Maher shelled and machinegunned Daraa's old quarter on Saturday. Syrian authorities said on Thursday the army had begun to leave Deraa, but residents described a city still under siege.

Troops were also deployed in the Damascus suburbs of Erbin, Saqba, Douma and in the town of Tel, north of the capital.

A senior diplomat said demonstrations after Friday prayers, the only chance Syrians have to gather legally, were expected to increase "incrementally, not massively" in numbers compared with a week ago when tens of thousands took to the streets.

'62 civilians killed'

Human rights campaigners say security forces killed at least 62 civilians, including 17 in Rastan alone, during those protests.

A doctor who planned to take part in Friday's demonstrations said "indiscriminate killings and inhumane arrests have generated total disgust among the average Syrian".

'Guns no longer a deterrent'

"Soldiers with rifles no longer deter people. The propaganda that this regime is the only guarantor of stability no longer washes," he said.

The United States, which had joined a European drive to improve ties with Assad under the Obama administration, called the attack on Daraa "barbaric".

Plot charge by Iran

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.

Iran, which the United States accused of helping Assad in his efforts to crush the demonstrators, said Syria's rulers were aware of plots by the United States and Israel to destabilise its only Arab ally.

An opposition figure said: "The international response is intensifying. But Assad will spill more Syrian blood before the world wakes up."

'At least 560 civilians killed in seven weeks'

Human rights campaigners say army, security forces and gunmen loyal to Assad had killed at least 560 civilians during seven weeks of pro-democracy demonstrations.

Thousands of people had been arrested and beaten, including the elderly, women and children, they said.

The authorities blame "armed terrorist groups" for the violence, including the killings of civilians and members of the security forces.

Syrian television showed what it said were confessions of terrorists arrested in Daraa and caches of weapons it said were seized.

'Foreign conspiracy'

Assad said the protesters were part of a foreign conspiracy to cause sectarian strife.

His father Hafez Al 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 Al Assad lost two wars to Israel, as defence minister in 1967 and as president in 1973. He maintained Syria's position as a relevant player in Middle East geopolitics by building ties with Shi'ite Iran and backing Palestinian guerrilla forces.

The younger Assad has reinforced the anti-Israeli alliance with Tehran, despite disquiet on the part of Syria's majority Sunni population.