A journalist is being investigated after publishing banned material in the Vincent Tabak trial on social network sites while the case was still active.

Police arrested the man, who has not been named, after he published secret details about porn films that the man found guilty of murdering Jo Yeates had been watching.

The evidence, which included films featuring women being strangled, had been ruled inadmissible during the trial by the Honourable Mr Justice Richard Field who had banned reporting of it until after the verdict.

The man was arrested during the trial after it was discovered that he had been posting information about Tabak’s porn habits on Twitter and Facebook.

The case is now being looked at under the Contempt of Court Act by the Government’s main legal adviser, Attorney General Dominic Grieve.

The Bristol Evening Post reported that details of the arrest emerged after reporting restrictions were lifted by the judge following the jury’s verdict.

Nicholas Rowland QC, junior prosecution counsel in the case, said: “A man who purported to be a journalist published material that was the subject matter of the first bad character argument.

“The papers are with the Attorney General and they are being considered.”