An American diplomat accused of possessing indecent images of children was "secretly flown out of the UK", according to reports.
US authorities allegedly raided the diplomat's London flat last month, seizing him and taking him to a US airbase for removal, The Sun reported.
US personnel have no powers of arrest in the UK and, The Sun reported, there was no formal request to extradite the man.
UK ministers are understood to be in contact with the US embassy over the incident.
The man's seizure is reported to be related to an investigation into another person in the US.
A Metropolitan Police spokesperson said: "On Tuesday August 25, US authorities made us aware of an investigation they are conducting into suspected offences in London relating to indecent images of children.
"We continue to liaise with them regarding this matter."
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A UK government spokesperson said: "We expect all foreign diplomats in the UK to abide by our laws, in the same way we expect all UK diplomats to do so when posted overseas.
"As a US investigation is ongoing, it would not be appropriate to comment further at this stage."
A US Embassy spokesperson told The Sun: "We are aware of allegations concerning an individual assigned to the Embassy. The United States government expects all personnel to adhere to the highest standards of conduct, and we take these allegations seriously."
In 2019, US official Anne Sacoolas left the UK after a car crash in Northamptonshire which killed 19-year-old Harry Dunn.
She was later convicted of causing his death - but did not return to the UK to attend the sentencing hearing in person.
Radd Seiger, a victim's advocate who worked with the Dunn family, told Sky News that if crimes are perpetrated on UK soil "that's where they have to be investigated".
He said: "Diplomatic immunity is a very important process that goes back over centuries and was designed to keep diplomats safe in hotspot countries, for instance, if they were taken hostage."
But he said it is "not a get out of jail free card" and diplomats should be subject to local, investigative processes.
(c) Sky News 2026: US officials 'secretly flew diplomat out of UK' after indecent image allegations
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