Syrian security forces continue to crack down on dissent, as protesters vow to hit the streets en masse to mark six months since the beginning of the anti-government uprising in March.
The planned protests against the rule of Bashar al-Assad on Thursday follow another day of killings, with human rights activists saying security forces shot dead eight people, including a child, in a huge sweep against anti-government protesters in northwestern Syria.
"Six months. More than ever determined to [continue] the March 15 uprising," activists wrote on the Facebook page for The Syrian Revolution 2011, one of the main online organisers for the protesters.
Armed with heavy machine guns, security forces cut off roads leading to the Jabal al-Zawiya villages of Baliun, Marayan, Ihsem, Al-Rami and Ablin, setting up checkpoints and arresting several people, the Britain-based Syrian Observatory for Human Rights (SOHR), said on Wednesday.
Four people were killed and dozens more wounded in the operation, activists said, adding that 100 people were arrested including the family of Riad al-Assad, a soldier who had earlier defected.
Elsewhere, a child was killed when security forces opened fire to disperse a demonstration in the village of Janudiya near the Turkish border, while another three people were shot dead in the central provinces of Hama and Homs, SOHR said.
The UN says a total of 2,600 people, mostly civilians, have been killed during the government's crackdown since the start of the uprising in March. Opposition activists put the death toll at more than 3,000.
Outside the violence-wracked country, Syrian dissidents were to gather in Istanbul on Thursday to unveil the makeup of a National Council set up to co-ordinate the movement against Assad's government.
Louay Safi, a US-based academic, told the Associated Press news agency that a group of activists will announce a 130-member council, made up of 60 exiled opponents and 70 dissidents inside Syria.
'Bus driver ambushed'
In other violence, the state-run SANA news agency reported that a bus driver was ambushed in the city of Hama by an "armed terrorist group," and that five soldiers and a guard who had been shot dead by a similar group were buried in Aleppo and Homs.
Syria has consistently maintained the protests are the work of "armed gangs", rejecting reports by Western embassies and human-rights groups that the great majority of those killed have been unarmed civilians.
The Syrian leadership has repeatedly said it is fighting a foreign conspiracy to divide the country and the authorities blame "armed terrorist groups" for the killings, including 700 members of the army and police.
In-depth coverage of escalating violence across Syria
In another development, Syrian state television announced on Thursday that it would be broadcasting the "confessions" of Hussein al-Harmoush - a lieutenant-colonel who appeared in a YouTube video in June and announced his defection from the Syrian army - during the evening news programme.
Al-Harmoush earlier managed to leave Syria and had been leading the Brigade of Free Officers, a group of dozens of officers who have deserted the regime.
However, according to opposition sources in Damascus, he was recently captured in Turkey by Syrian intelligence agents and brought back to Syria.
A week ago, three other military defectors were killed in Ablin when security forces raided the home of Mohammed al-Harmoush, the colonel's brother, SOHR said.
Al-Harmoush was abducted during the raid and "his body was returned to his family," Rami Abdel Rahman, the SOHR head, said.