VANDENBERG AIR FORCE BASE, Calif.—Three people were arrested for trespassing during a demonstration by peace activists outside the main gate at Vandenberg Air Force Base.

Sunday's protest marked 25 years of demonstrations against Vandenberg's testing of intercontinental ballistic missiles. About 110 people gathered along Highway 1 outside the main gate to hear speeches and sing songs.

Air Force security officers handcuffed three demonstrators who crossed a green line marking military property. They are expected to face federal trespassing charges.