A gun enthusiast who hoarded 950 rounds of live ammunition and tried to build an M16 assault rifle was ordered by a judge yesterday to undergo psychiatric assessment. Mr Justice Frank Stock said he needed to review psychiatric reports about Lam Yuk-fai before he could rule on whether the 20-year-old was 'an obsessed gun nut' or if 'in the background there is a lurking danger' to Hong Kong. 'It must be determined whether his gun enthusiasm crossed a particular border and posed any danger to society,' Mr Justice Stock said in the Court of First Instance. Lam, who is being held in custody, will be sentenced on May 7 after the judge sees doctors' reports. Lam pleaded guilty to possessing arms and ammunition without a licence in February this year. He admitted ordering ammunition and firearm parts from the United States, while the rest was bought via an unnamed Gurkha soldier in the SAR. His arsenal included assault rifle parts, 950 rounds of live ammunition and imitation guns and pistols. The cache was revealed on April 1 last year, when a neighbour in Lam's Kwun Tong building discovered it in a storeroom inside the building. The part-time university student used his income from his job in a gun shop and an allowance from his janitor father to build up the cache. Police examined his bank accounts and were satisfied Lam was not making money from re-selling arms, said prosecutor Daniel Ozorio. Government ballistics expert Andy Choi Wai-yee told the court that most of the guns and bullets in Lam's arsenal were not commonly used to commit crimes in Hong Kong. 'I tend to believe he's some sort of gun nut, but I think he is overdoing it considering the amount which was seized,' Mr Choi said. Lam has admitted using forged letterhead from a legitimate gun shop to order the gun parts from the US. Only registered gun dealers can import firearms. After Lam was arrested, Hong Kong police were notified by Interpol in Washington that a US arms vendor had received an e-mail order from 'Sam Lam' - the name used by Lam. He had allegedly asked the arms dealer whether it was possible to order gun parts by e-mail rather than post. He also allegedly requested all shipments be labelled 'machine parts', to avoid Hong Kong Customs problems, Mr Ozorio said. However, Lam denied sending the e-mail. Lam's e-mail account had 'been used with malicious intent by someone else', said Lam's lawyer, Paul Dinan. Lam will reappear before Mr Justice Stock on May 7.