An immigration officer yesterday gave the most detailed account yet of how last year's fatal Immigration Tower fire broke out, but disagreed with a defence counsel on who started the blaze. Choi Yue-ning, testifying at the murder-arson trial of seven abode seekers, said one claimant poured a bottle of fluid over his head, raised his left leg and set fire to it. 'The man became a fireball and there was the 'bomb' sound,' Mr Choi told the Court of First Instance. 'Once he lit the lighter, the fire started from his jeans and his whole body was on fire.' Referring to video footage of the incident, Mr Choi said the man in question was Pang Hon-kwan, 40, who was captured holding a bottle of liquid. Barrister Paul Dinan, for Pang, suggested to Mr Choi that he was mistaken and that the acts had actually been performed by Lam Siu-sing. Lam, 26, and senior immigration officer Leung Kam-kwong, 42, were badly burned in the blaze on August 2 last year and died in hospital nine days later. Mr Choi said he did not notice Lam during his time in Room 1301, Immigration Tower, as he was concentrating on Pang and co-accused Fu Mo, 39. He said Fu was raising an uncapped bottle when he and other offices moved into the room. Pang, Fu, Sze Kwan-lung, 24, Lam Hing-luen, 27, brothers Yeung Yee-ping, 29, and Yeung Yee-yim, 38, and Chau Hung-chuen, 30, deny two counts of murder and one of arson. The trial continues before Mr Justice Thomas Gall.