The son of the King of Bahrain could be arrested if he steps foot on British soil after the High Court ruled he was no longer immune from prosecution because of his royal status - if new evidence emerges.
Prince Nasser bin Hamad al-Khalifa is said to have been directly involved in the torture of three prisoners during a pro-democracy uprising in February 2011.
One prisoner, known only as FF who has been granted asylum in the UK, claims he was badly beaten - but not by Prince Nasser - and given a prison sentence after taking part in protests in the Gulf state, which have since left dozens dead.
FF now plans to provide the Metropolitan Police Service with evidence of the Prince's alleged actions.
However, the Bahrani government said the claims were unfounded and politically motivated.
In a statement, it added: "The situation has not, and will not, change as there is no evidence for the allegations."
Prince Nasser is a regular visitor to England and has met the royal family.
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