BREXIT will "unquestionably" hinder investigations of crimes with links outside the UK, Police Scotland's Deputy Chief Constable has said.

Warning cross-border investigations will be "less efficient and more cumbersome and bureaucratic" after Brexit, Will Kerr said British police forces will lose access to "vital" measures when the UK leaves the EU.

In a letter to Holyrood's Justice Committee, Kerr added the transition period allows for EU countries to refuse to extradite suspected criminals to face charges and possible trials in the UK.

Germany has already declared it will not be extraditing nationals, with Poland indicating it may follow suit.

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"Whilst the possibility of no-deal has been significantly reduced, we still stand to lose access to vital justice and home affairs measures post-December 2020, therefore we continue to prepare for a policing landscape devoid of these tools and implement plans to mitigate associated risks," Kerr wrote in his update to the committee.

He added: "The UK leaving the EU will unquestionably impact on our ability to conduct investigations and enquiries beyond our national borders.

"The justice and home affairs measures undoubtedly provide efficient and effective channels between law enforcement in the UK and the EU.

"Regardless of the final negotiated position on the future security partnership with the EU, Police Scotland will continue to work alongside partners in the EU, albeit this will be less efficient and more cumbersome and bureaucratic."