MAINLAND authorities have formed a group to investigate a Christmas Day traffic accident in Zhongshan in which a Hong Kong man and five mainlanders were killed. Hong Kong resident Leung Chiu-ming was killed along with five of his female work colleagues when the Jeep he was driving collided with a bus while the group was travelling on Qikong Highway on its way to Xinhui City from Zhongshan. A seventh Jeep occupant, another mainland female employed by the import-export company in Xinhui, was in hospital yesterday in coma. Compensation would be settled when the investigation finished, said a Zhongshan traffic police official.