Mexico drugs lord's release upsets US

The early release of a drugs lord, who spent 28 years behind bars in Mexico for kidnapping and murdering a US agent, has upset the US which has termed the move as "deeply troubling", BBC reported.

"The Drug Enforcement Administration was deeply troubled to learn of the decision by a Mexican court to release infamous drug trafficker Rafael Caro-Quintero from a Mexican prison," said the US Drug Enforcement Agency (DEA) in a statement Saturday.

It added that the Maxico court cut short Caro-Quintero's 40-year sentence for kidnapping, torture and murder of DEA Special Agent Enrique Camarena in Feb 1985.

The court ruled that Caro-Quintero, now 60, should have been tried in a state rather than a federal court.

The murder strained US-Mexico ties and changed the war on drugs trafficking.

Caro-Quintero is still listed as one of the DEA's five top international fugitives, and the US authorities believe he has been controlling drugs money from prison.

"DEA will vigorously continue its efforts to ensure Caro-Quintero faces charges in the US for the crimes he committed," the agency said.

Mexico's Attorney General Jesus Murillo Karam echoed those concerns, saying his office was analysing whether there were any charges pending against Caro-Quintero.

One of three founding members of the Guadalajara Cartel, Caro-Quintero had been arrested in Costa Rica amid a massive manhunt for cartel leaders.

The group was thought to be responsible for transporting the majority of the cocaine consumed in the US in the 1980s.