An investigation has been launched in a bid to find the source of a smear campaign targeting Labour parliamentary hopeful Cllr Tulip Siddiq – just days before the party picks its Hampstead and Kilburn candidate for the next general election.

Ham & High: Cllr Tulip Siddiq's aunt Sheikh Hasina, Bangladesh's prime minister, meets Prime Minister David Cameron at 10 Downing Street. Picture: PA/John StillwellCllr Tulip Siddiq's aunt Sheikh Hasina, Bangladesh's prime minister, meets Prime Minister David Cameron at 10 Downing Street. Picture: PA/John Stillwell (Image: PA Archive/Press Association Images)

On Wednesday of last week, an email relating to Cllr Siddiq and her family’s involvement in political life in Bangladesh was sent to every Camden councillor except Cllr Siddiq.

The email, which features a photograph of her alongside Russian president Vladimir Putin taken during a visit to see her family in Bangladesh, has been reported to Camden Council’s solicitor by councillors.

Cllr Siddiq, who represents Regent’s Park ward and is the niece of Bangladesh’s prime minister Sheikh Hasina, is vying with fellow Camden councillor Sally Gimson and Hackney Council deputy leader Sophie Linden to be selected as Labour’s parliamentary candidate for Hampstead and Kilburn at a hustings on Sunday.

Responding to the email, she said: “I think the claims are ludicrous, it has nothing to do with the work I’ve done in Camden as a councillor.

“I think it’s a group of bigoted people who don’t want a progressive woman like me to succeed.”

A source inside the council added: “No one believes there’s any validity in these claims. It smacks very much of dirty tricks.

“I’m confident that Tulip’s reputation won’t be diminished in the eyes of people who have paid attention to her political record.”

The council’s solicitor is attempting to unmask the email sender, who has also set up a Twitter account under the name “BdeshDynastyMonitor”.

Cllr Siddiq is the granddaughter of Sheikh Mujibur Rahman, Bangladesh’s first president, who was assassinated in 1975.

She is bidding for selection to challenge Conservative candidate Simon Marcus to replace retiring Hampstead and Kilburn MP Glenda Jackson in the 2015 general election.