President Reagan presented medals to former prisoners of three wars Friday and pledged continued efforts to bring home any more American prisoners of war who may be held.

"We write no final chapters here," Reagan told a crowd of approximately 1,000 at a medal ceremony on the South Lawn of the White House."Our country has not forgotten former comrades who are still missing, those who fought in Korea or Vietnam and have not returned home or been accounted for," the president said. "We must be faithful to them and their families and demand a full accounting of the fate of those Americans who are missing in action."

Reagan presented the medals to two prisoners from World War II, two from the Korean War and two from the Vietnam War as representatives of the many who are eligible.

The Defense Department began awarding the medals in April. They were authorized by Congress in the defense authorization act for the 1986 fiscal year.

Secretary of Defense Frank C. Carlucci told the crowd, "This is indeed a hard medal to earn. We hope that in the future we will not have to give out any more of these medals."

The recipients were Sgt. Albert J. Bland, retired from the Air Force, who served in the Pacific theater during World War II; Lt. Charles M. Williams, a retired Air Force officer who served in the European theater in World War II; Cpl. Charles A. Burton, who served with the Army in Korea; Col. Jesse Booker, a Marine Corps officer who Carlucci said was the first to be shot down and one of the longest-held officers in the Korean War; Col. Floyd James Thompson, an Army officer who was described as the first to be shot down, the longest held in the Vietnam War and who was held in the South; and Cmdr. Everett Alvarez, a Navy flier who Carlucci said was shot down over North Vietnam and was the second longest held prisoner of the war.