Animal rights campaigners whose protest was illegally stopped by police have called for an investigation and say they are considering legal action.

Fourteen members of Speak were cleared at Bicester Magistrates' Court on WednesdayMay30 of refusing to obey police orders during a protest against Oxford University's animal research laboratory.

District judge Deborah Wright found police had acted unlawfully in trying to break up the demonstration outside the Sheldonian Theatre, Broad Street, Oxford, last July.

Speak spokesman Mel Broughton said: "I hope someone, somewhere is going to make the very brave decision to investigate these officers thoroughly.

"I am certainly going to be looking at taking our own proceedings against the police.

"If the system in place won't do anything about it then we have to defend our basic rights - we are going to have to look for a way of doing it ourselves."

Thames Valley Police Deputy Chief Constable Alex Marshall has promised to review the case to consider disciplinary action against the officers involved.