University strikes turned violent as protesters stormed an academic building to demand that students in the lecture theatre join the walk out.

A demonstrator was allegedly attacked by a student during a clash in Sussex Univesity’s Jubilee Building, where a Psychology lecture was taking place.

“One of our marchers was assaulted by a student when we disrupted the lecture,” the Sussex Supports the Strike group wrote in a statement on their Facebook page.

“The marcher in question was violently tackled into a wooden table by another student," the group claimed.

Joanna Pawlik, an art history lecturer at the university, told The Telegraph: “We’ve had a lot of support from the students. We don’t like the way the pensions situation is being imposed on us which is why we have taken this action.”

A group of protesters gained access to the Universities UK (UUK) headquarters in central London, where they staged a sit-in.