LOS ANGELES (AP) _ The brother-in-law of a former Mexican president was found guilty Tuesday of racketeering, kidnapping and conspiracy in the death of U.S. drug agent Enrique Camarena.

Ruben Zuno Arce, a successful Guadalajara businessman, was the third defendant to be found guilty in a trial which sought to place blame on many in the 1985 kidnap-murder of Camarena and his pilot, Alfredo Zavala Avelar. He wasn't charged with murder.

The case has strained relations between Mexico and the United States because of U.S. officials allegations of complicity between Mexican officials and drug dealers.

Prosecutors said the slayings were revenge for Drug Enforcement Administration raids on marijuana and cocaine plantations that cost the drug barons $5 billion in profits.

Zuno is the brother-in-law of Luis Echeverria, the former president of Mexico. His lawyers maintained he had nothing to do with the Camarena affair and merely had the bad luck to sell his Guadalajara home to a drug kingpin who used the place as a torture chamber.

The key evidence against Zuno came from two government informants who were former Mexican policemen. One of them told of seeing Zuno at a meeting in which drug barons discussed the need to kidnap a drug enforcement agent.

The other witness told of alleged drug trade activities by Zuno. His lawyers claimed he was an upstanding businessman without ties to the underworld.

The same jurors previously convicted two other defendants of racketeering and kidnapping.

Juan Jose Bernabe Ramirez, a former Mexican policeman, was found guilty of kidnapping but innocent of murder on Monday. Last week, reputed drug baron Juan Ramon Matta Ballesteros was convicted of the Camarena kidnapping, but the jury also declined to convict him of murder.

One verdict remains pending against Javier Vasquez Velasco, who is accused of murdering two American tourists in an apparent mistake killing.

Jurors resumed their deliberations Tuesday afternoon following announcement of the verdicts and lawyers were told by U.S. District Judge Edward Rafeedie to refrain from commenting until all the verdicts were in.

Rafeedie scheduled sentencing for Zuno on Sept. 18. Zuno faces a maximum sentence of life in prison.

The 31-year-old Camarena was kidnapped off a Guadalajara street in February 1985. Testimony showed the agent was tortured and interrogated by drug lords before being slain along with Avelar.

Their bodies were found a month later on a ranch 65 miles from Guadalajara.

The trial was the second stemming from the Camarena murder, which strained U.S.-Mexican relations and embarrassed Mexico with testimony about dealings between corrupt law enforcement officers and drug dealers.

In a 1988 Los Angeles federal trial, two defendants were convicted of multiple charges, including murder, in the Camarena case and a third defendant was convicted of aiding the escape of Mexican drug lord Rafael Caro Quintero.

The DEA has vowed to capture every person involved in the slaying. So far, 22 people have been charged in this country. Over 20 have been imprisoned in Mexico.