(Bloomberg) -- A Guantanamo Bay prisoner suspected of terrorism is fighting to get his case heard in a London court after he alleged the UK was complicit in helping the US mistreat him. 

Abd al-Rahim al-Nashiri, a Saudi Arabian citizen, was first detained in Dubai in 2002 for his alleged involvement in two bombings targeting a US warship and a French civilian oil tanker. He’s been held captive in the Guantanamo Bay camp in Cuba since 2006. 

“There is an irresistible inference that the UK agencies participated in intelligence sharing in relation to the complainant and were complicit in his torture and ill-treatment,” Hugh Southey, a lawyer for Al-Nashiri, said in court documents prepared for a hearing Wednesday.

Al-Nashiri has already taken his claims of mistreatment to the European Court of Human Rights, while his separate US appeal over the use of torture was dismissed last year. Al-Nashiri lawyers said he faced waterboarding, mock executions, threats of death, sleep deprivation and rectal feeding.

Al-Nashiri was held in numerous “incommunicado detention” locations around the world and faced torture in secretive US Central Intelligence Agency sites, his lawyers said in their UK filings.

They’ve asked a London court to allow the case to proceed arguing that the UK, including security services and the defense ministry, participated in the US’s “high-value detainee program” and encouraged his historic mistreatment, according to the filings.

Lawyers for the UK agencies said that Al-Nashiri was held at all times by agents of another state, according to court documents.

At no point during the alleged mistreatment were any of the agencies present, they added. They argued the case shouldn’t take place in the UK, and so local human rights laws can’t be invoked. 

The UK’s defense ministry didn’t immediately respond to a request for comment. 

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