Syrian troops have stormed houses in and around a coastal village where government forces allegedly massacred at least 100 people, activists said on Friday, dpa reported.
The reports came after US Defence Secretary Chuck Hagel said that the administration in Washington was reexamining its opposition to arming Syrian rebels.
"You look and rethink all options," he said "It doesn't mean you do or you will. These are options that must be considered with the international community."
US President Barack Obama said his administration was taking a cautious approach, stressing the need for an "international consensus".
"We want to make sure that we look before we leap and that what we're doing is actually helpful to the situation, as opposed to making it more deadly or more complex," Obama said.
The British-based Syrian Observatory for Human Rights said troops and militants loyal to President Bashar al-Assad had conducted house-to-house searches and randomly arrested people in al-Bayda, a mostly Sunni Muslim village outside the coastal city of Baniyas.
The Observatory said more than 100 villagers had been killed in al-Bayda on Thursday. Many of those killed appeared to have been shot or stabbed, it said. The Military Council of the rebel Free Syrian Army said the death toll was 200.
Rami Abdel Rahman, head of the Observatory, told dpa that among those killed in al-Bayda were the village elder, Omar Bayassi, and his son.
Activists said troops attacked al-Bayda after a bus carrying pro-regime militants, known as Shabiha, was attacked, killing at least seven and wounding more than 30.
The opposition National Coalition denounced the al-Bayda attack and called on the Arab League and the United Nations to "act rapidly to save civilians in al-Bayda, Banias and other villages across Syria."
Its statement accused the Syrian government of committing "war crimes and genocide".
Meanwhile, human rights group Amnesty International has accused government troops and rebels of deliberately targeting journalists, in a report marking World Press Freedom Day.
It said that at least 36 journalists had been killed in attacks.
"Scores of journalists reporting on human rights abuses in Syria have been killed, arbitrarily arrested, detained, subjected to enforced disappearances and tortured over the last two years," said Amnesty's 56-page report, called "Shooting the Messenger."
"Abuses against journalists have been carried out both by the Syrian authorities and armed opposition groups, turning Syria into the deadliest country in the world," the report said.