A sprinkler system on board HMS Queen Elizabeth has been "inadvertently triggered", the Royal Navy has revealed.
It was confirmed earlier that the carrier would not be leaving Portsmouth today to continue its sea trials.
The largest and most powerful ship ever built for the Royal Navy, HMS Queen Elizabeth left her home port for the first time last May and arrived back home last November after conducting "successful sea trials".
It is understood the misfiring sprinklers were quickly isolated, the water stopped and cleared, and that some damage was caused in the hangar but not to the rest of the ship.
Believed to have happened on Sunday, it comes weeks after the aircraft carrier was found to have a leaking stern seal, which has now been resolved after repair work.
In response to the sprinkler incident, a Royal Navy spokesman said:
"We can confirm that following a routine exercise alongside, the fire warning system was inadvertently triggered on-board HMS Queen Elizabeth and some sprays activated, but she remains on track with her trials programme."
Earlier this month, Commodore Andrew Betton OBE, Commander of the Royal Navy’s Carrier Strike Group, said that the ship is 'helping to build global operational partnerships'.
The nation's future flagship has taken more than eight years to build and is the first of two new carriers built since HMS Ark Royal was scrapped in 2010.
She weighs 65,000 tonnes and has a top speed in excess of 25 knots.
Around 10,000 people worked on her construction, as well as a number of ship-building yards around the country.