The Papua New Guinea police have arrested an officer over accusations that police used bush knives to sever Achilles tendons of suspects as they were lying on the ground.
Three policemen are claimed to have carried out the violence on suspects who were apprehended in Port Moresby on Saturday.
The police were investigating a violent death and asked the suspects to walk to the Gordon police station because of transport problems.
On their way, the group was allegedly made to lie down and three officers cut the men's tendons.
Papua New Guinea police media relations officer Superintendent Dominic Kakas said an investigation is being carried out and the exact nature of the injuries is still being assessed.
Superintendent Kakas told Radio New Zealand's Morning Report programme it was not clear how many suspects were involved, as reports ranged from 20 to 70 people.
He said police had launched a modernisation programme just last month and thisi ncident has set police back years.