Eighteen people are still missing after two boats bumped into each other Saturday night in Hong Kong, Xinhua quoted local media as saying today. After spending the night searching for the missing, who were thrown into the water by the force of the collision, marine police and other rescuers had rescued seven people, including one Chinese and six Ukrainian of a tugboat, local media reported. The accident occurred near the Brothers, an island group located between Tun Men and the Hong Kong International Airport, at around 1300 GMT Saturday when a container-carrying freighter and a tugboat collided. The tugboat, carrying 25 people on board, sank shortly after the collision and dozens of people were believed to be trapped in its cabin. Meanwhile, all the 25 seamen boarding the freighter, registered on the Chinese mainland, were safe. The Hong Kong Special Administrative Region (HKSAR) government has mobilized the marine police, fire fighters, frogmen and a helicopter, to search for the missing amid foggy weather conditions. Local media said if the 18 missing have drowned, the collision would be the worst maritime disaster for decades in Hong Kong. The Marine Department had warned ships sailing on Hong Kong's waters on Saturday morning that visibility was as low as 740 meters.