Three men who say they were stripped naked, assaulted, dragged along the ground, had bags placed over their heads and threatened with rape and drowning during an anti-war protest in Victoria have today launched legal proceedings to compel the government to release the identities of the soldiers involved.

The pro bono legal action was launched in Melbourne this morning by Maurice Blackburn lawyers, the firm active in representing asylum seekers on Nauru, and which scored a major victory for Traditional Owners last year in fending off a nuclear waste dump in the Northern Territory.

In October last year, Sam Quinlan, Greg Rolles and David Sprigg – part of a group of peace activists known as the Swan Island Peace Convergence – swam to the Swan Island military base from Queenscliff to stage a peaceful protest against Australia’s involvement in foreign wars.

Soon after arriving on the island, the men were confronted by a number of unidentified defence personnel.

The protestor’s lawyer, Maurice Blackburn principal Jacob Varghese said the three men clearly stated they were non-violent protestors, however they were “thrown to the ground and dragged, had bags put over their heads and were stripped naked. One was threatened with rape and another with drowning”.

The proceedings were filed in the Victorian Supreme Court to force the Australian Defence Force and the Commonwealth to provide the names of the officers involved in the incident, after the ADF refused repeated requests for access to the information.

Mr Varghese said the identity of one was provided, and when the other identities are discovered the men intend to sue for assault and battery.

“These men are peaceful protestors who were prepared to accept the lawful consequences of their actions, but they did not deserve this violent assault on their dignity,” Mr Varghese said.

“The protestors experienced brutal, degrading and humiliating treatment at the hands of Defence Force personnel. This kind of behaviour cannot go unanswered.”

In a written statement, Sam Quinlan said his group had been shocked by the actions of the military personnel.

“It was very clear that we were there as non-violent peace activists. The officers’ response to our peaceful protest was excessively violent and completely unwarranted.”

Greg Rolles said the protestors had decided to take legal action to make sure the officers involved were held to account for their behaviour.

“If this is how these officers treat Australian citizens on Australian soil, what’s happening to people in other parts of the world that we don’t know about?”