The controversial Mayor of Tower Hamlets was "brainwashed" by Muslim fundamentalists before running for office, it was claimed today.

Labour politician Helal Abbas said he thought that "fundamentalists" had been "using" Lutfur Rahman, whose re-election in Tower Hamlets is subject to a High Court challenge.

Mr Abbas's concerns emerged when he gave evidence at the hearing in London today.

He revealed them in a written witness statement given to Election Commissioner Richard Mawrey, who is presiding over a trial in an Election Court.

Four Tower Hamlets voters have accused Mr Rahman, an independent, of "electoral fraud" at the Election Court trial.

The group of four - headed by Andy Erlam, who stood as a Tower Hamlets councillor on an anti-corruption ticket - has mounted a challenge under the provisions of the 1983 Representation Of The People Act.

Evidence is being outlined to Mr Mawrey - a senior lawyer sitting as a judge - at a hearing expected to last several weeks.

Mr Mawrey has been asked to declare the result of a May 2014 mayoral election, which saw Mr Rahman elected for a second term, void and order a re-run.

Lawyers for the group of four have made series of allegations - including "personation" in postal voting and at polling stations and ballot paper tampering.

Mr Rahman says there is "little if any" evidence of wrong-doing against him.

His lawyers have described the group of four's claims as "invention", "exaggeration" and "in some cases downright deliberately false allegations".

Mr Rahman had been leader of the Labour group on the council between 2008 and 2010, Mr Mawrey has heard.

He had gone on to found a party called "Tower Hamlets First".

Mr Abbas, a former leader of Tower Hamlets Council, said his "brainwashing" concerns dated to a time when Mr Rahman was a member of the local Labour Party.

He said - in a statement made in 2010 - that Mr Rahman had been associated with the Islamic Forum of Europe (IFE).

"IFE is a Muslim fundamentalist organisation," said Mr Abbas in the 2010 statement. "It is a sophisticated international operation."

He added: "In my opinion, Lutfur Rahman has been brainwashed by fundamentalists and they (were) using him for the purposes of entry into the Labour Party."

The hearing continues tomorrow.