SAN SALVADOR, FEB. 3 -- The Roman Catholic archbishop of San Salvador, Arturo Rivera y Damas, said today that a church investigation of the killing of 15 peasants two weeks ago indicates that Salvadoran army soldiers were responsible.

In his Sunday homily, Rivera y Damas said a 17-page report by the Catholic Church human-rights office pointed "exclusively to the responsibility of members of the 1st Infantry Brigade in this crime, which was committed with total impunity and also has the characteristics of the death squads."

Children who survived the massacre described how armed men dressed in black uniforms came to the hamlet of El Zapote late on the night of Jan. 21. The youngsters watched from hiding as their parents were stabbed and their throats were slit. The victims, including a 14-year-old girl, were all from the same family.

Rivera y Damas said there was sufficient evidence for the judicial authorities to focus their investigations within the armed forces. Initially, surviving family members suggested that the killings may have resulted from an inter-family feud. But some now blame the army.

"It was the soldiers," said Eleuteria Ortiz, 88, who was told to leave by the attackers. "They were cleanly shaven on the backs of their necks," she said. Other family members saw insignia on the uniforms, according to the church group.

The army has denied that soldiers were involved in the killings, pointing out that the victims had relatives in the army. Leftists guerrillas, however, say that one of those killed was a guerrilla combatant and that the family were rebel collaborators.