THE driver of a speedboat with two illegal immigrants on board rammed his 10-metre vessel into a small police rubber craft in a bid to escape, killing one officer and severely injuring another, the High Court heard yesterday. The court was told that Sergeant Put Yam-chiu was thrown overboard and died when a fractured rib penetrated his lung. Sergeant Cheung Wai-lun sustained severe brain damage and would not be able to give evidence in court. Appearing before Mr Justice Stock is Chan Heung-kui, also known as Lau Pan, 26, who denied the manslaughter of Sergeant Put and wounding Sergeant Cheung with intent to resist arrest. But he had pleaded guilty to a charge of abandoning a vessel within Hongkong waters without lawful excuse. In his opening address, senior Crown Counsel Mr John McMaster told the jury that officers on a police launch patrolling the vicinity of Lamma Island spotted a suspicious object on the radar at about 9 pm on September 23, 1991. Two rubber craft were sent to investigate. One of them, PV55, was manned by Sergeant Put and Sergeant Cheung and the second one, PV4, was operated by Sergeant Li Kam-fai and Constable Law Hip-chung. About 90 metres from the object, Mr McMaster said, they let off flares to illuminate the area and saw a 10-metre speedboat with four large outboard motors. The court heard that the boat, heading towards Pak Kok, accelerated and the police craft gave chase, during which the speedboat abruptly turned, resulting in a head-on collision with PV55. Mr McMaster said Sergeant Put suffered severe injuries and was thrown into the sea. He was later certified dead. The cause was a fractured rib penetrating his lung. Sergeant Cheung also sustained serious wounds, including a fractured skull and severe brain damage, said counsel. Mr McMaster said that after the collision, two more police launches joined the chase. Suddenly the speedboat slowed down, allowing the police launches to catch up, he said. Two men were seen jumping into the sea. One was Chan, who was rescued and apprehended, he said. The hearing continues.