Syrian security forces have killed at least 34 people, including an 11-year-old boy, according to witnesses, in the latest crackdown on anti-government protests.

Twelve people were killed in the central city of Homs, while 15 died in the town of Maaret al-Naaman, located near the western city of Idlib, activists said.

Two protesters were shot in the southern region of Deraa, one person was shot in the Damascus suburb of Daraya and one in the port city of Latakia.

Two more died in the eastern town of Deir Ezzor and one person killed in the central town of Hama.

The dead in Homs included two boys, named as Aiham al-Ahmad, 11, and 16-year-old Ahmad Bakr, witnesses said.

A witness told Al Jazeera they were shot when police officers opened fire on Friday, after their vehicle crashed into a wall and was attacked by protesters.

The attack took place after officers drove police cars into a crowd of about 2,000 demonstrators in an attempt to disperse them, a second witness said.

After hitting several protesters, one of the cars crashed into a wall, prompting the officers to jump out and open fire. Four other protesters were also killed, while at least seven others were wounded.

In a separate incident, three residents were killed when security forces attempted to storm a hospital in the al-Wa'r neighbourhood of Homs, according to a witness.

Locals responded by forming a human chain around the hospital, in an attempt to prevent the police arresting wounded protesters inside. The witness said some locals had shot at the police using handguns.

Al Jazeera is unable to verify the reports because of restrictions on reporting imposed by Syria's government.

'Four killed' in Berze

Security forces also opened fire on protesters in Berze, a suburb north-east of Damascus, killing four protesters and wounding tens, a witness told Al Jazeera.

"The protesters have all been shot in the legs and stomach," he said.

The protest began after Friday prayers when around 1,000 people marched through the streets, chanting "peaceful, peaceful" and calling for the toppling of the regime.

The witness told Al Jazeera that security forces had first attacked and beaten protesters with sticks and had then fired tear gas at them.

"Then they opened fire on us," he said, the sound of gunshots audible over the phone line as he spoke.

After the killing, security forces began detaining people, he said. "People are afraid to go home for fear of being arrested."

Berze was surrounded by police checkpoints and electricity to the town had been cut, he said.

A video uploaded to YouTube earlier appeared to show protesters in Berze using alleyways to protest, which activists said was a new strategy to avoid coming under fire from snipers, as is reported to have happened during previous protests. Al Jazeera cannot independently verify the video's contents.

Assyrian Christians arrested

In Qamishli, Syrian security raided the headquarters of the Assyrian Democratic Association and arrested 12 of its members, according to two activists who spoke to al-Jazeera.

It was the first crackdown by security forces on the widespread participation of Assyrian Christians in the democratic uprising.

Khodr Abdel Karim, a human rights activist in Qamishli, said: "This is a message from the regime to Syrian Christians not to participate in any of these demonstrations. It is the duty of every Syrian to claim them back from this arrest."

Syria has launched a bloody crackdown over the past two months in response to an unprecedented uprising against Bashar al-Assad, the country's president. Human rights groups say more than 850 people have been killed.

Syria has blamed the unrest on armed thugs and foreign agitators.

According to organisers, there were also protests on Friday in the Mediterranean port of Baniyas, the central city of Hama and the coastal city of Latakia.

The Syrian Observatory for Human Rights said gunfire was reported in Baniyas. Another person was shot in Sanamin, a village near the southern flashpoint city of Deraa, it said.

There were more reports of violence in Damascus, the Syrian capital, where a witness told Al Jazeera that regime supporters with iron bars had attacked a group of 500 to 700 worshippers as they left the Dahabiyyeh mosque in the Old City, after Friday prayers.

In Midan, a conservative Sunni neighbourhood of Damascus, a demonstration by Abu Ayoub al-Ansari mosque had barely begun when security forces fired tear gas on around 1,000 protesters, arresting several, a witness told Al Jazeera.

'Azadi Friday'

The Kurdish-majority areas of Syria's northeast saw smaller than expected numbers of protesters, according to a Kurdish political activist, despite nationwide demonstrations being dubbed by organisers as 'Azadi Friday', the Kurdish word for freedom.

About 6,000 demonstrated in Amouda while smaller crowds gathered in other towns in the region.

The numbers were larger than last Friday but fell short of the expectations of organisers who had hoped the Kurds, who have not faced the same level of armed crackdown as protesters elsewhere in Syria, would take to the streets en masse.

An activist said state employees in the region had been warned they would lose their jobs if they took part in protests.