SAN DIEGO (AP) – The USS Midway Museum has been evacuated as crews fight a fire on board the historic aircraft carrier in San Diego.

City Fire-Rescue spokesman Lee Swanson says the blaze was reported around 5:30 a.m. Wednesday on a lower deck, possibly the one just below the flight deck.

Swanson says the fire appears to be at a construction site aboard the ship. He didn’t know how many people were on board when the blaze broke out but said the ship was evacuated.

No injuries have been reported.

The museum opened in 2004 and hosts as many as a million visitors a year. It has about 200 employees and 650 volunteers.