HONG KONG (REUTERS) - Hong Kong police charged two boat captains with manslaughter on Thursday in connection with a ferry collision last year that killed 39 people in the city's worst maritime disaster in decades.

The two were released on HK$20,000 (S$3,192) bail each on condition that they do not leave Hong Kong. The case was adjourned to May 9.

A commuter ferry and a company boat carrying more than 120 staff and family to watch fireworks in the city's Victoria Harbour collided on the evening of Oct 1 and the leisure vessel sank quickly.

The company boat belonged to Hongkong Electric Company, which is controlled by Hong Kong's richest man, Mr Li Ka-shing, and was taking passengers to celebrate the mid-autumn festival.

Hong Kong is home to one of the world's busiest shipping lanes and, while serious accidents are rare, the waters have become increasingly crowded with leisure boats and vessels that ferry passengers to the nearby gambling hub of Macau.