A mahjong parlour worker has been arrested after police swooped on a Yuen Long flat that doubled as a veritable arsenal, seizing more than 500 weapons inside.

Officers made their move as the man left his Tong Tau Po village dwelling on Tuesday morning.

A total of 562 weapons, including 115 that are expressly prohibited – brass knuckles, flick knives, butterfly knives, nunchucks and extendable batons – were found inside the flat.

They also seized 11 high-powered laser pointers, five crossbows with arrows, 431 knives of different styles and sizes and a number of swords.

The 55-year-old man was arrested for possession of prohibited weapons, possession of offensive weapons and possession of arms without a licence.

Police are investigating if he has triad links.

Chief Inspector Kammy Tsui Ka-wing of Border district said the weapons were sourced from foreign countries and an investigation showed the man had been selling them over the past month via online trading platforms, though there were fewer than 10 transactions.

Police believed the sold items had not been used in the past year’s anti-government protests, but the motives of the buyers would be part of the investigation, she added.