SAN DIEGO -- The USS Ronald Reagan and three warships in its strike group returned to San Diego Wednesday following a five-month deployment that included air strikes in support of U.S. forces in Afghanistan and operations against pirates off Somalia.

Thousands of family members lined the docks at Naval Air Station North Island to greet the arrival of the nuclear-powered aircraft carrier and at Naval Base San Diego to welcome home the crews of the guided-missile cruiser USS Chancellorsville and the guided-missile destroyers USS Gridley and USS Howard.

There are more than 5,000 sailors and aviators on the four ships, which form part of the U.S. Navy's Carrier Strike Group 7.

Two more ships in the group -- the guided-missile destroyer Decatur and guided-missile frigate Thach -- will remain in the Persian Gulf before returning to return to San Diego next month, according to the Navy.

The USS Ronald Reagan and its air wing -- the ship can carry 85 warplanes -- operated for more than two months in the 5th Fleet and 7th Fleet Area of Operations, which encompasses the Persian Gulf, Red Sea, Gulf of Oman and parts of the Indian Ocean.

From the Gulf of Oman, it provided 30 percent of all air support to U.S. and coalition ground forces in Afghanistan, with the air wing flying more than 1,600 sorties, according to an article on the Navy Office of Information Web site.

"Ships of the Ronald Reagan Carrier Strike Group were also vital in counterpiracy and maritime security operations off Somalia and the Horn of Africa," it said, adding that they also "protected vital Iraqi infrastructure" at the northern tip of the Persian Gulf.

"Every single sailor knew how vital the mission was to accomplish," said Capt. Kenneth Norton, the Ronald Reagan's skipper.

The Reagan is scheduled to undergo a $12.1 million, seven-month-long systems upgrade.

The planned makeover will be carried out in San Diego by personnel from Northrop Grumman Shipbuilding of Newport News, Va. It will include inspections and tests of all systems and components as well as repairs and alterations.

The Ronald Reagan is scheduled to be ready in May for its next deployment.