STUDENT campaigners have complained to Edinburgh University over the policing of a sit-in protest over the institution's stance on fossil fuel investments.

Concerns were raised after a security guard outside the protest was filmed on a camera phone lifting a protestor away from a doorway as other students are heard telling him: "That's an assault."

The security guard then dragged another protestor away, appeared to topple over on top of him and was then filmed with his hand on his neck as he lay on the ground.

He was then ushered away by another security guard as students told him: "You can't do that. Get your hand off."

Later, the campaigners, who have occupied a management building at Edinburgh University for over a week, hit out at the institution's attempt to "shut them up with violence".

Eric Lai, one of the occupiers, said: "We have been repeatedly told that the university supports our right to protest, but that couldn't feel further from the truth.

"The university have posted dozens of guards on the doors and have now taken to intimidation and violence to shut us up. It is hard to imagine a more inappropriate way to handle student protest.

"The university need to immediately change their approach, allowing open access to the building and engaging with the politics of why we're here, rather than just covering their ears to both the demands of students and staff, and the desperate urgency of tackling climate change."

The incidents occurred as students who were unable to get into the building where the sit-in is being held held a picket outside as part of a protest at the university's refusal to divest from fossil fuels.

Last week, the institution said it would continue investing in companies that produce fossil fuels, but would work with them to reduce emissions.

A University of Edinburgh spokesman  said: "The University is aware of, and deeply regrets, the unfortunate incident that is currently being played on social media.  The matter is now in the hands of the police. 

"We continue to support the right of students to peacefully and lawfully demonstrate and the University is using private security outside its buildings in Chambers Street in order to secure the safety of staff and students during the occupation.

"We are constantly reviewing our security arrangements to make sure that they are appropriate to the circumstances in what is an evolving situation."

A University of Edinburgh spokesperson said: "The University is aware of, and deeply regrets, the unfortunate incident that is currently being played on social media.  The matter is now in the hands of the police. 

"We continue to support the right of students to peacefully and lawfully demonstrate and the University is using private security outside its buildings in Chambers Street in order to secure the safety of staff and students during the occupation."

"We are constantly reviewing our security arrangements to make sure that they are appropriate to the circumstances in what is an evolving situation."