Police overpowered a 43-year-old man who allegedly harassed his Vietnamese former girlfriend on a regular basis, arming himself with knives and a fake gun that had been reconfigured to fire bullets.

The man, who has the surname Lin, was already wanted by police on outstanding drug charges when he was arrested in Changhua.

According to police Lin was frequently making unwelcome visits to a  woman called Ho in the hope of rekindling their romance, the Apple Daily reported. The relationship had ended in July.

Reports suggest that Lin became emotional and violent when he was with Ho, and wielded a knife. Police had difficulty tracking him down because he often changed the number plate on his motorcycle.

However, officers set an ambush when Ho told them Lin had returned, and took him into custody. Lin had mistakenly assumed that the police had already left the house occupied by Ho. The reconfigured pistol and bullets were recovered from his motorcycle.