Fourteen civilian commandos surrendered early Tuesday after holding off hundreds of tank- and artillery-backed soldiers and police at an army base for a day, the government news agency said.

At least 25 people were killed in fighting after about 40 commandos, who the government said were leftist guerrillas, broke through the base's main gate in a stolen truck early Monday, authorities said.The state-run Telam news agency said 13 men and one woman walked out of the base early Tuesday, their hands in the air and one waving a white shirt as a flag of surrender.

Sporadic shots and mortar rounds were heard for about an hour afterward, but two hours later all was silent. President Raul Alfonsin was en route to the scene, said his press secretary, Jose Ignacio Lopez.

The red brick officers' club in which the attackers holed up was virtually leveled by tank and mortar fire, and the woman who surrendered was wounded and carried out by two comrades, Telam reported.

Soldiers took the 14 into custody and entered the bombed-out officers club, it said.

Troops issued an ultimatum through loudspeakers to any other commandos who might be on the base in La Tablada, on Buenos Aires' western outskirts. Local news reports said some commandos had sniped at police and troops Monday from positions outside the base.

The commandos had been reported earlier as holding hostages, but reports Tuesday did not mention captives.

Five soldiers were killed and more than 30 soldiers and police officers wounded in Monday's battle, Telam reported. Carlos Becerra, an aide to Alfonsin, said at least 20 commandos were killed.