A London borough mayor, accused by the Government of allowing anti-Semitism to “fester”, has been found guilty of corruption and illegal practices by an Election Court judge.

Lutfur Rahman was elected mayor of Tower Hamlets, a borough in east London, in May 2014 with a 3,000 vote majority, but the election has now been declared void. His time in office has been filled with controversy including raising a Palestinian flag above the Town Hall and accusations of close links with Islamic extremist groups.

The ruling follows a November report, commissioned by the Government, which according to the Daily Telegraph accused him of electoral fraud, cronyism and religious extremism, prompting a police investigation and leading Eric Pickles, Secretary of State, to take direct control of Tower Hamlets council and.

Eric Pickles, who presented the findings to the House of Commons, explained that Mr Rahman’s administration had allowed anti-Semitism and religious extremism to “fester”.

The legal challenge to his election had been brought by four voters and lawyers for the group, after making a series of allegations, including “personation” in postal voting and at polling stations, and ballot paper tampering.

He is also alleged to have threatened council staff and bribed religious groups, telling electors that voting for him would be a “virtuous and Islamic act” while threatening his opponents with punishment in the afterlife.

Election Commissioner Richard Mawry said: “The court is satisfied that corrupt and illegal practises were extensively prevalent and it may reasonably be supposed to have affected the result of the election.

The May 2014 mayoral election will now be re-run and Rahman is barred from standing, the judge said. He was also ordered to pay £250,000 costs.

Mr Rahman, who was Britain’s first elected Muslim mayor, denies the claims.