Hatred and threats towards the Ahmadiyya community even infected the general election race in Tooting.

Since being re-elected in May with a slim majority of 2,524 after fierce opposition from Conservative candidate Mark Clarke, Sadiq Khan has gone on to become Shadow Justice Secretary.

But Nasser Butt, who stood against him for the Liberal Democrats and is an Ahmadi, spoke out about a campaign to prevent him being elected because of his religion.

An election hustings at the Tooting Islamic Centre (TIC) on April 14 turned into a dangerous farce after hardliners shut down proceedings.

After arriving at the TIC, mixed-race Tory candidate Mark Clarke had to be locked into a room for his own safety after he was mistaken for Mr Butt by fundametalists.

Mr Clarke’s election agent, Andre Walker, said: “We had to be locked in a room for our own security. The mosque committee were embarrassed by it and it was tense for a while...it was clear Nasser’s arrival would have been dangerous and a real problem. There was anger an Ahmadi was running.”

During the incident, Mr Butt said he received a phone call from a committee member who told him it would be best if he did not come to speak as had been arranged.

It has also emerged worshippers were given precise orders at the TIC to urge Muslims not to vote for Ahmadi candidates.

A secret recording of a meeting at the TIC, two days before polling day on May 3, revealed Imam Suliman addressed the meeting alongside Harris Bokhani, speaker from an unknown organisation.

Mr Bokhani is heard to tell the audience: “The majority of Muslims in this area are voting Lib Dem, because they think Nasser Butt is a Muslim.

“If you don’t go in and speak to them, they’re not going to do it. They’re fed up of hearing it from the imams. They want to hear it from you. They need to you go into the community and say ‘Why are you supporting the Qadiani community?’”

Mr Khan told this paper last week he was not aware of the incident until days later and did not know about the pair being locked in a room.

He rejected claims the Muslim vote played an important role in his re-election, claiming he had support from faith leaders across the religious spectrum.

He said: "It's really important everyone in the community gets along. One of the hallmarks of Tooting is that people with different rules and religions have got along so well for so long.

"If there's any section of our community that feels vulnerable or discriminated against, there’s a responsibility on the rest of us to reach out and ensure this doesn’t happen.

"There are theological differences but we shouldn’t just tolerate each other, we should respect each other.

"My job as MP is to represent everyone in the community, irrespective of the size of the community and religious beliefs."

TIC Imam Suliman Gani told us this week: “We never recommend any political candidate on religious grounds.

“Like all organisations, we only recommend political candidates based on how their stated policies affect our community.

“The Ahmadiyya community has been actively distributing leaflets claiming they are the only Muslims who love peace and harmony and thereby maligning the vast Muslim community.

“So, as an example, unless an Ahmadi candidate renounced such maligning of Muslims by the community he belongs to, we would not recommend him as he/she would be antithetical to the perception of our peace-loving community in such delicate times.”