A member of the Royal Marines Band due to perform at the King’s coronation has had his trombone stolen.

The instrument, which police said is “of huge sentimental value”, was in the boot of the serving marine’s car when the vehicle was taken from Princes Risborough Station car park in Buckinghamshire last month.

British Transport Police (BTP) have said the car is still missing on the eve of the coronation, and appealed for help to reunite the man with his trombone.

Officers believe the vehicle was taken within a 23-hour window from 3pm on April 12.

The Ministry of Defence has said the marine used a replacement trombone for coronation rehearsals.

A spokesman for the department said: “A trombone was reported as stolen from a member of the Royal Marines Band Service on April 13.

“The instrument has been replaced with no impact to coronation rehearsals.”

The trombone has the serial number 186905 on the mouthpiece and BTP asked for anyone with information to contact them on 61016.