Syrian security forces shot dead at least five people, including a child, as pro-democracy protests swept the country on Friday after weekly prayers, with demonstrators calling for more freedom in defiance of a fierce crackdown, witnesses said.

The child and three other people were killed in the central city of Homs. Another person was shot dead in Sanamein, a village in the southern region of Daraa, epicentre of protests that have gripped Syria since March 15, they said.

Protests were also held in other regions, including the coastal city of Banias where a witness said security forces fired shots to disperse the crowd. It was unclear if there were any casualties.

A militant reported that a demonstration was held outside a mosque in central Damascus but it was quickly dispersed by the security forces.

In Ain Arab, a mainly Kurdish region near the northern city of Aleppo, hundreds took to the streets holding olive branches and chanting, "No to violence, yes to dialogue" and "We are not Islamists or Salafists, we want freedom," said Radif Mustapha, head of a Kurdish rights group reached by telephone.

"No one is calling for the downfall of the regime," he said, as the demonstrators could be overheard shouting, "azadi, azadi," or freedom in Kurdish.

In Banias, thousands of men, women and children marched, with many of the men bare-chested to show proof they were unarmed, Rami Abdel Rahman, of the London-based Syrian Observatory for Human Rights, told AFP.

Hassan Berro, an activist, said protests took place in several towns and villages in the northeast of the country, including Qamishli, Amuda and Derbasiyeh. Several arrests were reported in Qamishli.

The accounts could not be independently verified as foreign journalists are prevented from travelling in the country to report on the unprecedented protests that have been met with brutal force despite mounting international pressure on the authoritarian regime of President Bashar al-Assad.

Crucially, both Damascus and Aleppo have so far been largely spared the unrest and it is widely believed that should massive demonstrations begin there that would mark a serious setback for the regime.

In a keynote speech on Thursday on the Middle East, US President Barack Obama urged Assad, who is facing the greatest challenge to his 11-year rule, to lead a political transition or "get out."

"President Assad now has a choice," Obama said in his speech. "He can lead that transition or get out of the way.

"The Syrian government must stop shooting demonstrators and allow peaceful protests."

Damascus, however, defiantly rejected the warning, countering that Obama's appeal was not aimed at easing tensions in Syria but rather at sowing discord.

"Obama is inciting violence when he says that Assad and his regime will face challenges from the inside and will be isolated on the outside if he fails to adopt democratic reforms," the official news agency SANA said.

The government newspaper Al-Thawra also criticised the US president saying: "He (Obama) didn't forget his arrogance in telling a sovereign country what to do... and threatening to isolate this country if it fails to do as told."

More than 850 people have been killed and thousands arrested since the protests began in mid-March, according to human rights groups and the United Nations.

Assad's government has blamed the violence on "armed terrorist gangs" backed by Islamists and foreign agitators.

A confident Assad earlier this week said he believes the unrest was coming to an end and, in an unusual step, acknowledged wrongdoing by the country's security services.

The protests have posed the greatest challenge to nearly five decades of rule by his Baath party, which is controlled by members of the minority Alawite community, an offshoot of Shiite Islam.

The majority of Syria's 23-million population are Sunni Muslims.

Western powers initially were hesitant to criticise Assad's regime due to Syria's strategic importance in the region and fears of possible civil war if the regime were to collapse.