Philippine police have arrested five Chinese nationals who tortured a Chinese man in order to force his relatives back home to honor the man’s gambling debts.

On Wednesday, ABS-CBN News reported that the Philippine National Police Anti-Kidnapping Group (PNP-AKG) had arrested the five Chinese on Monday after a sting operation disguised as a ransom payoff.

Police said Chinese national Si Yuxiang was illegally detained by the five on Friday when he couldn’t make good on debts he’d incurred gambling at an unspecified casino. However, the sting operation in which the undercover cops met with the kidnappers occurred at the Solaire Resort & Casino in Manila’s Entertainment City gaming zone.

Si and two of the gang’s other victims were taken to a safe house in the province of Laguna, the site of Si’s torture. The precise mechanism of Si’s abuse went unreported, but police noted that they’d found a taser at the safe house, along with guns and handcuffs.