Britain's police watchdog will investigate London's Metropolitan Police over a 2019 letter, The Guardian and BBC News report. The letter made claims about Thomas Markle, the father of the Duchess of Sussex.

The Independent Office for Police Conduct said the force's "failure to pass on allegations of serious offending" to authorities abroad at the time needed a full inquiry, the outlets report. The Met had referred itself to the watchdog, The Guardian and BBC News report.

The letter was written by Markle's former wife, Roslyn Loveless, and sent to the Met's royal protection team, the outlets report. The Met said it held claims about crimes outside the UK, The Guardian and BBC News report. The force said it passed the letter to the office of the Duke and Duchess of Sussex. The Met says it is now sending the details to agencies overseas, the outlets report.

Markle faces claims in the Philippines that he had images of child sexual abuse, which he denies, the outlets report. BBC News reports he has called the claims "sick lies." His son, Thomas Markle Jr., handed material to police in the Philippines, who are investigating, the outlets report.

The watchdog will not look into a separate question about a possible data breach, the outlets report. It sent that matter back to the Met.

What we know: The watchdog will investigate why the Met did not share the 2019 letter's claims with police overseas.
What we don't: What the letter said in full and what police in the Philippines will find.