Çakır was stripped in 2015 of both her Olympic and European 1500m titles and received an eight-year ban for anomalies in her athlete biological passport (ABP).

This was later reduced to four years and she was eligible to compete again officially from this year as the start date of the ban was backdated to 2013.

Çakır took part in the European Champion Clubs Cup Cross Country event in Portugal in February, finishing in 11th place and helping her Istanbul team Uskudar Belediyespor win the title.

Turkey's state-run Anadolu news agency has now reported she has committed another offence and is being banned for life as it is her third offence.

Çakır previously served a two-year ban for a positive test at the 2004 International Association of Athletics Federations (IAAF) World Junior Championships.

Details of her later offence have not been made public by the Turkish Athletics Federation.

"We are never, ever going to allow doping," said TAF President Fatih Cintimar

"And everyone must know that,"

It is surely the final chapter in the extraordinary career of 32-year-old Çakır.

She had taken the World Anti-Doping Agency (WADA) to the Court of Arbitration for Sport  after she claimed she should be given a reduced sentence because she revealed sons of former IAAF President Lamine Diack had told her in 2012 that she could keep her London 2012 1500m gold medal if she paid them a bribe of €650,000 (£490,000/$700,000).

WADA admitted she had given "valuable substantial assistance" but "did not agree to grant a further reduction to her suspension" after they had already agreed to suspend four years of her ban in 2015.

It came as a result of her providing evidence which was used as part of the Independent Commission report, published in November.

The women's 1500m at London 2012 is widely considered one of the dirtiest races in history.

Turkey's Gamze Bulut should have moved up to the gold medal after Çakır's disqualification, having originally finished second, but was also stripped of her silver after she was implicated in a doping scandal due to problems with her ABP.

It means the first two places in the race remain vacant.

Several other athletes in that race have also since been suspended for drugs or have been linked to doping.

Turkey has one of the worst doping records in athletics.

Elvan Abeylegesse was also stripped earlier this year of the two Olympic silver medals she claimed at the Beijing 2008 Olympics over 5,000m and 10,000m after her samples for those Games was re-tested. 

insidethegames has contacted the Athletics Integrity Unit for a comment on Çakır.

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