The trial of an animal rights activist accused of conspiracy to burn down parts of Oxford University collapsed yesterday after the jury failed to reach a verdict.

Supporters of Mel Broughton wept in court as he was found not guilty of possessing an explosive substance with intent – despite him having packets of sparklers hidden in his home.

The jury failed to reach a verdict on the two other charges against the 48-year-old however; of conspiracy to commit arson, and possession of an article or articles with intent to damage or destroy property.

Broughton had been on trial at Oxford Crown Court for the previous two weeks on charges of waging a ‘terrorist campaign’ against the University’s plans to build a controversial animal testing laboratory.

A re-trial is now expected to take place early next year.

The charges related to a fire that ripped through a sports pavilion owned by The Queen’s College in 2006. Two other unexploded bombs were also found underneath a portacabin used by the then Templeton College, in February 2007.

Broughton, aged 48 years, was charged after the seemingly innocent items were found concealed in an old water tank in a shared bathroom at his home.

Police claimed they were to be used in attacks on the two Oxford colleges in protest at the building of the controversial research laboratory in South Parks Road.

During the trial, Broughton admitted the sparklers were his and that he had hidden them away.

The outspoken veteran activist claimed he was under such intense pressure and monitoring by police that he was paranoid and not thinking straight when he concealed them.

He had bought the sparklers from a firework shop near his home, in Northampton, with the aim of using them at one of the weekly protest vigils at the lab site in Oxford, he told the court.

He explained to the jury that he was “too high-profile” to risk carrying out the attacks as he was a well known activist.

His defence barrister David Bentley also said that the police had been waging a “dirty war” against his client.

Prosecuting, John Price, told Oxford Crown Court that Broughton was the founder and “a leading light” in the protest group SPEAK, labelling him as a self proclaimed animal rights “fanatic.”

However, after nine hours and 28 minutes of deliberations, the jury returned the not guilty verdict on count three.

Judge Patrick Eccles QC asked the foreman if further time would help the jury reach a verdict on the remaining two charges to which the foreman replied that it would not.

The judge told the jury: “I am going to discharge you from returning any further verdicts.”

Prosecuting, Ian Hope, asked the judge for a retrial on the two remaining counts, which is expected to take place in the new year.

Supporters and members of Broughton’s family gasped as the not guilty verdict was read out and one female in the public gallery burst into tears.

Broughton, of Semilong Road, Northampton, was remanded in custody for a further hearing at Oxford Crown Court within the next two weeks.

Defending, David Bentley, said he would like his client’s custody reviewed at the next hearing, in the light of the jury’s not-guilty verdict.