Police are risking "another Ian Tomlinson" with their approach to the tuition fee protests, a student leader has claimed.

Simon Hardy, co-organiser of the National Campaign Against Fees and Cuts, said it was only a matter of time before somebody was killed on one of the recurrent demonstrations.

Giving evidence to MPs and peers on the Joint Committee on Human Rights, he criticised the Metropolitan Police for "kettling" and using violence during recent protests around Westminster.

He insisted there was "an absolute democratic right" to protest but that police tactics could result in the death of a demonstrator.

Mr Hardy cited the case of Alfie Meadows, the 20-year-old who needed brain surgery after allegedly being hit by a police truncheon during the December 9 demonstration.

The Met faced heavy criticism after newspaper vendor Ian Tomlinson died after being hit by a policeman during the G20 protests in London last year.

Aaron Porter, president of the National Union of Students, asked the committee to investigate claims that police used aggression against protesters during the November 24 demonstration.

Mr Porter also criticised the use of kettling, describing it as "an unnecessary use of force" which was not "conducive to creating a calm and peaceful protest".

Chris Allison, assistant commissioner at Scotland Yard, said kettling - or containment - had only been used as "a last resort" during the student protests.