A 21-year-old man accused of carrying an air gun on a Hong Kong MTR train and stealing a police book on April Fool’s Day was arrested on Monday. The Hongkonger, who is unemployed, was detained at about 6pm after police raided his home in Sheung Shui. As of noon on Tuesday, the suspect was still being detained at Central police station and had not been charged. Police said the investigation was ongoing. Hong Kong Police Force rolls out the big guns for President Duterte’s visit On April 1, police were called to Admiralty MTR station at about 3pm following reports of a man holding a suspected air gun on board an Admiralty-bound train. Officers scouted the platforms and concourses at Admiralty and Central stations and nearby areas but could not find the man. Initial investigations indicated the same man was suspected to have stolen a police check-in book at Kowloon Tong MTR station about half an hour later, police said. Officers use the book to record station checks. Hong Kong police urged to step up training after officer warned over botched evidence collection After reviewing closed-circuit television footage to gather evidence and identify the suspect, police raided a flat in Sheung Shui at about 6pm on Monday and arrested the man for possession of an imitation firearm and theft. Police said no air gun or “pistol-like object” was found in the flat.