Indonesian police arrested five policemen on Thursday over the alleged torture of militants after a video posted on YouTube showed a suspect being shot and others abused.
The blurry 14-minute video posted by several Islamic groups on their websites and YouTube depicts officers forcing a man to strip to his underwear before they shoot him, apparently in the chest.
"We arrested five policemen today and others are still being questioned," national police detective chief Sutarman said in a text message, without giving further details.
He said earlier that the video was a compilation of two separate incidents, one from 2007 and another from 2012, and that a total of 16 officers were under an ongoing investigation.
Almost all the armed officers, wearing bullet-proof vests and helmets, were identified as members of the anti-terror squad Detachment 88, while several were from the police's elite Mobile Brigade, police had said.
The incident occurred in Poso, a known hotbed for militant activity on the island of Sulawesi where police have become the main target of militants and several bomb plots have been foiled.
The video sparked outrage among activists and Islamic groups, and there are concerns about retaliatory attacks in Poso, where two officers investigating an alleged militant training camp in October were found buried with their throats slit.
A consortium of Islamic organisations on Thursday called for an evaluation and audit of the elite unit, which it accused of torture and extrajudicial killings.
"If these steps are not carried out, then the unit should be dissolved. We're concerned Indonesian Muslims will become sympathetic to terrorists if such police action continues," Din Syamsuddin, chair of the country's second-largest Muslim organisation Muhammadiyah, told reporters.
Detachment 88 was set up with US and Australian help after the 2002 Bali bombings that killed 202 people, followed by a string of other deadly attacks targeting Westerners which were mostly blamed on the Al-Qaeda-linked group Jemaah Islamiyah.
It has been on the frontline of a crackdown on terrorism which has weakened key militant networks.