A Royal Navy senior rating is being investigated after reportedly turning up for duty on a nuclear powered-submarine after drinking.
The chief petty officer was escorted off 5,200-tonne HMS Talent, undergoing a refit at Devonport in Plymouth.
A navy spokesman said there was no danger to anyone as a result of the incident on the Christmas Day evening.
He added that the Trafalgar-class submarine's reactor was shut down during refit.
The chief petty officer, understood to be in his 40s, lives off the base, and is part of the duty navy crew working on the submarine alongside civilian contractors.
The marine engineer did not take over his duty post as someone enquired into his condition as soon as he got on board the vessel.
An investigation was immediately started by Royal Navy Service Police. It is due to finish end of month, the navy spokesman said.
He added that the rating was still reporting for duty in the meantime.
HMS Talent has been in refit for the past year. The work is expected to take another 12 months to complete.