32 dead, 170 unaccounted for after Philippines boat collision

(CNN) -- Two days after the ferry they were on sank after colliding with a cargo ship, 170 people remained unaccounted for Sunday morning in waters between southern Philippine islands, a Coast Guard official said.

Authorities have found the bodies of 32 people and rescued another 629, said Coast Guard spokeswoman Dawn Baterbonia.

The incident occurred around 9 p.m. Friday in the Mactan Channel about 2 miles northwest of Cebu City, the capital of Cebu province.

The passenger ship -- MV St. Thomas Aquinas -- was coming from nearby Butuan City and the cargo ship -- the Sulpicio, which had about 20 people aboard -- was leaving Cebu for the province of Davao in Mindanao.

The passenger ferry sank, but not before sending out a distress call heard by Coast Guard officials.

The cargo vessel involved in the crash -- along with Navy, Coast Guard and commercial vessels -- was helping in the rescue efforts.

The incident recalls one of the worst maritime disasters in world history dating to December 20, 1987, also off the Philippines.

Between 1,700 and more than 4,000 people were killed when the ferry Dona Paz collided with the tanker MT Victor. The number of casualties has varied; many claim the Dona Paz was extremely overcrowded.

CNN's Greg Botelho and Sara Mazloumsaki contributed to this report.