For a year the Clinton administration has presented the stunning arrest of Mexico's drug-enforcement chief as proof of that government's strong will to fight corruption. But now U.S. analysts have concluded that the case shows much wider military involvement with drug traffickers than the Mexican authorities have acknowledged.

According to an extensive classified report by the Drug Enforcement Administration and other intelligence assessments, the arrest last year of the former official, Gen. Jesus Gutierrez Rebollo, followed secret meetings between Mexican army officers and the country's biggest drug mafia, officials say.Exactly what transpired remains unclear. But the officials say there is growing evidence that military officers discussed a deal to let the drug gang operate in exchange for huge bribes and that some such arrangement may have been in place before the gang's leader, Amado Carrillo Fuentes, died after extensive plastic surgery last year.

The Gutierrez Rebollo case initially raised fears that he might have passed sensitive intelligence to members of Carrillo Fuentes' gang. But U.S. officials say it now points to the possible collusion of military officials who are central to U.S. drug-enforcement efforts in Mexico.

Some intelligence experts have questioned aspects of the report, officials said, describing them as speculative. But drug-enforcement authorities still presented it to Attorney General Janet Reno and other senior officials Feb. 6, one year to the day after Gutierrez Rebollo was arrested on the orders of the Mexican defense minister.