AGANA, Guam (AP) _ A ''terrorist theat'' which the Navy would not explain forced elaborate secuity during the change of command ceremony Friday for the military's top commander in Micronesia.

Dozens of military security men, armed with automatic weapons, surrounded the headquarters of the U.S. Naval Forces Marianas command as Commodore Chauncy Hoffman assumed the post from Commodore Dale Hagen.

Guests, including invited dignitaries, went through a cordon of bomb- sniffing dogs before they were seated the headquarters building. The visitors included Federated States of Micronesia President Toswio Nakayama, Guam Congessman Ben Blas, Republic of Palau Airai State Gov. Roman Tmetuchl, Guam Gov. Ricardo Bordallo and Pohnpei Gov. Resio Moses and other representatives of Micronesian nations and states.

Sweeps of the thick jungle surrounding the area, atop Guam's Nimitz Hill, had begun early Thursday.

Navy Chief Jeannie Campbell, spokewoman for the command, would say only that there had been a 'terroristic threat,'' and that it was being taken seriously. She refused to elaborate.

Security for military and island leaders has increased since the assassination of Palau President Haruo Remeliik on June 30.

In his farewell speech, Hagen said he is concerned that developing nations of Micronesia may be tempted to seek out alliances with nations other than the United States.

''The United States might have to engage in battle for the hearts and minds of the Micronesian people,'' Hagen said.

He urged the Micronesian leaders at the ceremony to ''beware of false and shallow promises.''