A U.N. agency says as many as 10,000 Palestinians have “disappeared” after fleeing a refugee camp in the Syrian port city of Latakia, where government security forces have carried out days of deadly attacks.

U.N. Relief and Works Agency Spokesman Christopher Gunness told VOA Tuesday the refugees fled the camp Monday under heavy gunfire and that the agency has “no idea” where they are.

He called for urgent access to the camp, which houses a health clinic, schools and youth programs, and said humanitarian workers need to tend to the sick, the dying and the needy.

The agency has not received a response to its request for access, but Gunness says it hopes to hear in the next day or two.

Rights activists reported heavy gunfire Tuesday in Latakia, marking the fourth day of an assault against anti-government dissent. The activists say security forces have killed at least 30 people there since Saturday.

Meanwhile, Turkey has warned neighboring Syria that its military operations against civilians “must end immediately and unconditionally.”

Turkish Foreign Minister Ahmet Davutoglu said Monday this “is our final word to the Syrian authorities.”

In Houla, a town near the city of Homs, activists said Syrian troops backed by tanks carried out raids and arrests Monday.

Latakia and Homs are among the Syrian cities that have seen large protests demanding the resignation of President Bashar al-Assad.

The Turkish foreign minister visited President Assad in Damascus last week to urge an end to his brutal crackdown against the anti-government uprising. Mr. Davutoglu said Monday that unless the bloodshed ends immediately, there will nothing left to discuss with Syrian authorities.

Activists and witnesses say Syrian gunboats joined tanks in firing on Latakia Sunday, a new element in the government's crackdown that has been escalating since mid-March.

Syrian officials have given a different account of events in Latakia. They deny the city was shelled from the sea, and say that naval vessels were on routine duty to protect the coast and prevent arms smuggling.

On Sunday, Syria's state-run news agency said law enforcement personnel were pursuing gunmen who it said were terrorizing residents of Latakia.

Details of events in Syria are difficult to verify independently because the government allows very few foreign news reporters into the country and restricts their movements.

Rights groups and activists say at least 1,700 people have been killed since the start of the government's crackdown.