A Labour Party candidate for the council by-election in Alperton is understood to have been suspended by his party as it investigates alleged anti-Muslim tweets.
In recent months, posts on Twitter, seen by the Times, apparently by candidate Chetan Harpale, accuse Pakistan of being a "Terror State" and suggest that party leader Jeremy Corbyn is "pro-jihadist".
The Twitter account is now locked and despite approaches by the Times, neither Mr Harpale nor representatives of the Labour Party have given any comment on the posts.
A Labour Party spokesperson said it couldn't comment on the particular case but added: "The Labour Party takes all complaints of this nature seriously, and they are fully investigated in line with our rules and procedures and any appropriate action is taken."
The by-election has been called in Alperton after Labour councillor James Allie resigned.
The Times understands Mr Allie has also been suspended by the Labour Party.
The tweets by @HarpaleChetan include one written on August 12 which reads: "#CorbynAniIndia-Projihadis Alienating British Indian Labour supporters? #CorbbyAniIndiaProjihadis @jeremycorbyn @UKLabour @JKSC_UK."
In another, @HarpaleChetan writes: "This is so called Peacefully Religion!!!! #PakistanTerrorState #JammuAndKashmir."
He also expressed admiration Harrow MP Bob Blackman, a right-wing pro-Modi Conservative and former leader of Brent Conservatives,
Green Party Andrew Linnie said he is "shocked and disgusted by the racist, Islamophobic views aired".
He said: "I think it is important, given the hostility of the language used, that Labour leader Cllr Butt not only condemns these views but withdraws support from this inappropriate candidate from the election while there's still time."
Cllr Muhammed Butt, leader of Brent Council, was approached for comment.
As well as Mr Linnie, Harmit Vyas of the Conservative Party is standing for Alperton on January 23, as is Anton Georgiou for the Liberal Democrats.
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