A POLICEMAN plotted with an armed gang to help a friend escape from police custody, the High Court heard yesterday. But the friend's liberty was short-lived as he was shot dead by police in a siege a few days later, Deputy Judge Cheung and a jury were told. Wong Chi-yun, 28, who had been a police officer for more than six years, suggested that Lo Sai-on feign illness so he would be taken to hospital as it was easier to free him from there. A gang armed with firearms, tipped off by Wong, held Lo's police escorts at gunpoint at the hospital and grabbed their revolvers, the court heard. Wong faces six conspiracy counts; one of conspiring to help Lo Sai-on escape from custody, two of conspiring to rob two police officers of their firearms and three of conspiring to falsely imprison three police officers. He has denied all charges. The court heard that the first attempt to spring Lo the day after his arrest on July 20, 1991, failed because when Lo complained of stomach ache and was taken to the Prince of Wales hospital, the gang was not organised. Lo was taken back to Tin Sum police station in Sha Tin. But Wong and the gang decided to try again, and in the early hours of the next day Lo complained a headache and dizziness and this time all went according to plan, the court heard. Lo was freed from police custody in the early hours of July 22, 1991, by his friends. Three police officers were imprisoned and two of them had their revolvers stolen. Opening the Crown's case, Stevan Cole said Wong did not take part in the actual release of Lo so he was charged with conspiracy. But he had suggested many details of the plot which was actually carried out and had played a big role as he was the one withinside information. Wong often went out socially with Lo, and in fact they had been out together just 12 hours before Lo was arrested by other police officers on July 20, 1991, for breach of a supervision order, Mr Cole said. Wong went to the scene of the arrest, but did not acknowledge that he knew Lo, the court heard. Mr Cole said evidence would show that Wong provided friends with details of the arrest and how to escape and he suggested Lo should complain of sickness so he would be taken to hospital as it was easier to help him escape from there. He said police managed to track Lo and other gang members down a few days later at an address in Shui Tau village, Yuen Long. Lo and another gang member were killed in the ensuing siege and gunbattle. The hearing continues.