SINGAPORE - An unemployed man was fined $1,000 on Tuesday (March 14) for displaying threatening behaviour by taking out a realistic looking replica gun in public and cocking it.

Alarmed by Timothy Tan Zhiyu's behaviour, a passer-by informed the police.

As a result, about 50 police officers from different departments including Ang Mo Kio Police Division, the Criminal Investigation Department, the Special Tactics and Rescue team and the Special Operations Command were mobilised in an urgent operation.

The court heard that Tan, 26, who used to work as a vessel traffic controller with the Maritime and Port Authority of Singapore, has been a cosplayer for many years.

Tan, who enjoyed dressing up as a Swat officer and a US Marine, bought several plastic toy guns to feed his interest.

On Sept 23, 2015 he was walking alone towards an open air carpark near Block 331 Yishun Ring Road at around 9.45am when he decided to fiddle with his replica gun which he had tucked down the front of his pants.

He took it out, cocked it as he would a real weapon, and concealed it underneath his clothes again.

Deputy Public Prosecutor (DPP) Joshua Rene Jeyaraj said Tan did not think anyone noticed him playing with the replica weapon.

However, the passer-by spotted his antics.

DPP Joshua added: "Alarmed that the accused seemed to be in possession of a real handgun and seemed to be parading it in public in such a cavalier manner, (the passer-by) immediately called the police.

"Given that it seemed that the accused was in possession of a real handgun and the current security climate, an urgent police operation was mounted to determine the accused's whereabouts."

The officers involved had to comb through CCTV footage from various HDB blocks in the neighbourhood and interview scores of people. After they identified Tan holding his replica gun in a CCTV footage captured in a lift at Block 331 Yishun Ring Road, they raided his home and arrested him.

Court documents did not reveal his address.

After his arrest, officers realised the weapon was only a replica, made of hard plastic and incapable of firing projectiles. The court heard that in all, police seized 14 replica rifles and two replica handguns from Tan's home.

Tan told them he bought the replica handgun at a shop known as Black Tactical.com at Funan DigitaLife Mall, which is now the subject of a police investigation.

DPP Joshua told District Judge Imran Abdul Hamid that police have since raided the store for suspected breaches of the Regulation of Imports and Exports Regulations (REIR).

Tan, who was unrepresented, said in mitigation that he was sorry for what he had done and was not thinking when he took the replica gun out in public.

According to an amendment to the REIR made in 2015, toy and replica handguns are controlled imports and can only be brought into Singapore if approval is granted by Customs and the Police Licensing and Regulatory Department.

For displaying threatening behaviour with the replica gun, Tan could have been fined up to $5,000.