LOS ANGELES, NOV. 14 -- Secret indictments have been issued against three key suspects in the death of U.S. drug agent Enrique Camarena, but announcement of the action has been delayed to avoid upsetting the negotiations for a criminal justice treaty with Mexico, it was reported today.

A Mexican federal judicial police commander, a major drug trafficker and his cousin were indicted by a federal grand jury in Los Angeles May 13, capping a two-year investigation of the 1985 slaying in Mexico, the Los Angeles Times said.

The charges were to have been unsealed late last month, but were held up by Associate Attorney General Stephen S. Trott because of concerns about the effect on a proposed U.S.-Mexico treaty on the exchange of evidence in criminal cases, officials told the newspaper.

The delay has frustrated U.S. officials involved in the high-priority probe who are eager to begin prosecution.

Camarena, a Guadalajara-based agent for the U.S. Drug Enforcement Administration, was kidnaped at gunpoint outside the U.S. consulate in Guadalajara on Feb. 7, 1985. His body and that of an associate were found about a month later.

Rafael Caro-Quintero, whose drug ring allegedly lost billions of dollars worth of marijuana because of DEA investigations, has been charged with the kidnap and murder of the two men. Armando Pavon Reyes, a federal police commander who headed the investigation into Camarena's kidnaping, and Caro-Quintero's cousin, Ines Calderon-Quintero, have been charged with hindering and preventing his apprehension.