SAN DIEGO -- The San Diego-based aircraft carrier Ronald Reagan and seven other Navy ships were headed for earthquake-ravaged Japan on Saturday to help with relief efforts.

"People are in trouble and frequently countries look to us for assistance," Capt. Jeff Breslau, speaking from Hawaii for Pacific Fleet, told The San Diego Union-Tribune. "It's second nature for us when there is a crisis to switch to that mindset."

Along with three members of the Reagan Carrier Strike Group, the Essex, Harpers Ferry, Germantown, Tortuga and Blue Ridge are traveling to the disaster site, Breslau said.

All the warships are scheduled to reach Japan within about 24 hours.

Naval personnel may help with logistics, moving people and supplies, medical assistance, creating communications systems, search-and-rescue operations and building shelters.

They may also help provide fresh water. Watermakers aboard the Reagan can produce up to 400,000 gallons of water daily, Breslau said.

The warships on their way to Japan were in the western Pacific on other missions when the quake struck at 9:46 p.m. Thursday Pacific time.