A leftist Argentine linked to the assassination of former Nicaraguan dictator Anastasio Somoza played a role in Monday's 30-hour rebel seizure of an army base that left 38 people dead, a senior government official said Thursday.

Officials also reportedly displayed Soviet, Chinese and U.S. weapons the rebels used to capture La Tablada infantry base 12 miles south of Buenos Aires, and said police were forming an elite commando unit in Buenos Aires province to fight terrorism.Also Thursday, mothers of people who "disappeared" during the military's "dirty war" against suspected subversives during the 1970s said Monday's rebel attack would benefit the military and the government.

Hebe de Bonafini, president of the Mothers of Plaza de Mayo, told a rally by her group, "Now, the torturers, the murderers, will become heroes."

Attorney General Andres D'Alessio said veteran rebel Enrique Gorriaran Merlo, who fled Argentina in 1976, played an "important role" in the pre-dawn raid Monday when rebels began a 30-hour seizure of the base.

Thirty-eight people died, more than 50 troops and police were wounded and 14 rebels were captured. Ruling party congressman Juan Carlos Pugliese, who cited a "failure in intelligence" that left officials unprepared for the attack, said Thursday that 28 of the 50 rebels died, eight fled and the rest were captured.

Before Gorriaran, 47, fled Argentina, he was a leader in the People's Revolutionary Army guerrilla group, thought to have been decimated during the "dirty war."

Argentine and Paraguayan intelligence officials later linked him to the 1980 assassination of Somoza in Asuncion, Paraguay, where Somoza was living after he was ousted in the 1979 Sandinista revolution.

After democracy replaced Argentina's military regime in December 1983, President Raul Alfonsin ordered the capture and prosecution of several former military and guerrilla leaders - including Gorriaran.

Officials said Wednesday one of the attackers killed when troops recaptured La Tablada was Gorriaran's lawyer, human rights activist Jorge Manuel Banos.