Hundreds of Sunni Muslim families fled Syria's coastal town of Banias yesterday, fearing further sectarian violence after fighters loyal to President Bashar al-Assad killed dozens of people overnight, according to activists.

The activists said the killings in the Ras al-Nabaa district of Banias took place two days after state forces and pro-Assad militias killed at least 50 Sunnis in the nearby village of Baida.

The Syrian Observatory for Human Rights, a pro-opposition monitoring group, posted a video online showing the bodies of 10 people it said were killed in Ras al-Nabaa – half of them children.

Some were lying in pools of blood, and one toddler was covered in burns, her clothes singed and her legs charred.

Activist reports and videos on the killings could not be independently verified as the Syrian government restricts media access.

The two-year-old uprising against four decades of Assad family rule has been led by Syria's Sunni Muslim majority, and sectarian clashes and alleged massacres have become increasingly common in a conflict that has killed more than 70,000 people.

Minorities such as the Alawites, an offshoot of Shi'ite Islam, have largely stood behind Assad, who is from the Alawite sect.

Banias is a Sunni pocket in the midst of a large Alawite enclave on Syria's Mediterranean coast, and activists in the area accuse militias loyal to Assad of ethnic cleansing.

"I estimate that hundreds of families left and headed for nearby towns like Jableh and Tartous," said Rami Abdelrahman, head of the British-based Syrian Observatory.

"But now the army is turning people back at the checkpoints outside the town, telling them to go back to Banias, that nothing is wrong. There are also announcements going out on mosque loud speakers telling people to return home."

Another video posted online by activists showed what they said were the bodies of 20 people killed in Banias overnight, all from the same family, including women and nine children.

The observatory blamed the killings on the National Defence Forces (NDF), a new paramilitary group made up mostly of fighters from minorities that back Assad.

Meanwhile, in another escalation of the crisis, Israel has carried out an air strike in Syria targeting a shipment of missiles bound for Hezbollah guerrillas in neighbouring Lebanon, an Israeli official said yesterday.

Israel had long made it clear it is prepared to resort to force to prevent advanced Syrian weapons, including Assad's reputed chemical arsenal, reaching his Shi'ite Muslim Hezbollah allies or Islamist insurgents taking part in the uprising.

Hezbollah, allied with Israel's arch-enemy Iran, waged an inconclusive war with the Jewish state in 2006 and remains a potent threat in Israeli eyes. Israelis also worry that if Assad is toppled, Islamist rebels could turn his guns on them after four decades of relative calm in the Golan Heights border area.

The target of Friday's raid was not a Syrian chemical weapons facility, a regional security source said.

A US official had told reporters on Friday the target was apparently a building.

In January, Israel bombed a convoy in Syria, apparently hitting weapons destined for Hezbollah.

■SYRIA