BEIJING - President Hu Jintao, Premier Wen Jiabao and Vice-President Xi Jinping on Tuesday expressed condolence over Monday's deadly ship collision in Hong Kong and urged the HK government to spare no efforts to rescue the missing people and comfort the victims' families.

Hu, Wen and Xi had all made calls to learn about the relief work.

They urged the maritime rescue center and other involved departments to fully cooperate with the Hong Kong government in rescue and provide all the help needed.

The central government had asked neighboring Guangdong province to send four salvage vessels to help Hong Kong police with rescue work after the accident occurred.

Other leaders, including State Councilor Liu Yandong, had also convoyed sympathy to the injured and the families of the victims of the collision.

A ferry and a pleasure craft collided off Lamma Island to the southwest of Hong Kong Island at about 8:23 pm on Monday evening.

A condolence ceremony will be held on October 4 across Hong Kong and Hong Kong regional flags at government buildings will be at half-mast for three days starting Thursday.