Syrian government forces shelled a vulnerable Sunni community in a coastal province dominated by President Bashar Assad's Alawite sect on Saturday, activists said, raising fears that residents of the isolated town could face mass killings by pro-Damascus militias.

Two Syrian rights groups said shelling of the town of Al-Mitras began at dawn, killing six people. The town lies near two other Sunni Muslim towns of Bayda and Banias. Rights groups charge that regime supporters killed at least 248 people in those two communities in May. They said regime forces shelled Bayda before militias entered and carried out the alleged massacre.

"We are worried, because this is an isolated area and crimes can be covered up quickly," said Rami Abdul-Rahman of the British-based Syrian Observatory for Human Rights, which follows a network of activists in the field. He said the shelling began at dawn after rebels were spotted nearby.

Syria's civil war has cleaved along the country's sectarian patchwork. Sunnis dominate the revolt, while Christians and other Muslim sects have mostly stood behind the regime.

Another Syrian activist who goes by the name of Abu Al-Waleed said there were negotiations underway to hand over rebel fighters in exchange for regime forces promising not to allow harm to come to civilians.

"The fear is that they are trying to clean this area of rebel supporters — that is, the Sunni community," he said in a Skype call.

Also in Syria, the government raised the price of gasoline and transportation in its latest wartime austerity move, a step likely to increase hardship for many Syrians already suffering from the economic consequences of civil war.

The price hike was announced late Friday.

The price of a liter (quarter-gallon) of gasoline increased by 25 percent, from 80 Syrian pounds (45 cents, on the black market) to 100 (57 cents), according to a government declaration. Official Imad Al-Assil said the decision would simultaneously raise transportation fees by 17 percent.

The consequences of a gasoline price rise are likely to be most punishing for Syrians living in rebel-held regions, where fuel is smuggled in, or rushed through unsafe roads. It can be up to three times as expensive as in the government zones.

The increase will also impact the price of food due to increased transportation costs. International groups say that rising prices has already made it difficult for Syrians to afford food, and activists have reported pockets of malnutrition in rebel enclaves like the suburbs of Damascus.

Any increases will also likely raise heating costs for many city households, which use gasoline-powered generators to cope with frequent outages.

Syria has been importing gasoline to make up for a shortfall in local production, interrupted by the two-and-a-half year conflict. It last raised the price of gasoline in May.

The conflict has shattered Syria's economy, killed more than 100,000 people and forced over 2 million from their homes.