Batu Pahat police also took part in the 1.30am operation on an entertainment centre in Taman Bukit Pasir, Batu Pahat, Johor.

“A total of 21 people were inspected, and the team saved two 17-year-old Laotians, believed to be victims of human trafficking,” Harian Metro reported a source as saying.

“The inspections resulted in the arrests of 15 people, including a 56-year-old woman believed to be the ‘mummy’ for the GROs,” he said.

The source said those arrested comprised six Vietnamese nationals, five Laotians, two Myanmar citizens, one Bangladeshi, and a local, all aged between 18 and 56.

Police believe the premises had been operating for the past seven years as a karaoke business, offering customers the services of foreign waitresses.

The place was equipped with closed-circuit television cameras and had several secret rooms and spaces to hide its GROs in case of police raids.

The source said the premises had a valid business licence, but operated beyond the allowed hours until 6am every day.