Mexico OKs U.S. Overflights to Detect Drug Smugglers : Narcotics: The arrangement is hailed as a breakthrough. Move is aimed at stemming cocaine shipments from Colombia.

WASHINGTON —  In what U.S. officials hailed as a significant breakthrough, Mexico permitted the U.S. Customs Service on Friday to resume surveillance flights over its territory aimed at detecting planes smuggling cocaine from Colombia to the United States.

Under the arrangement disclosed by Jorge Carrillo Olea, Mexico’s new top drug official, as he was completing a week of meetings here, a Mexican pilot will be aboard all flights by the P-3 surveillance aircraft to assure that the planes’ radar is turned on only over international waters.

The flight paths were changed last summer, reportedly because Mexico saw an infringement on its sovereignty when U.S. radar was used over its territory.

U.S. Customs Commissioner Carol Hallett said that she was “absolutely delighted” with Mexico’s approval of the overflights. The agreement will shorten P-3 flights by eight hours. That is the extra time it has taken the surveillance planes to fly around Mexican territory on their way to the Pacific area where they track clandestine flights from Colombia.

The radar-equipped aircraft can remain in the air 12 to 13 hours, Hallett said, so the saving of eight hours adds significantly to their surveillance time.

“The longer the observation, the greater the benefit,” Carrillo Olea told reporters at Mexico’s Embassy here. He made clear that he is not concerned that the P-3s might attempt to gather other intelligence from Mexico with their sophisticated sensing devices. Mexico’s foreign ministry requested that a Mexican flier be on the planes, he said.

Carrillo Olea said that the decision to allow the P-3 flights had been made before he came to the United States on Monday and that the first flight was crossing Mexico en route to the Pacific Ocean as he met with reporters.

The Customs Service P-3s are based in Corpus Christi, Tex., and had been flying to San Diego and then down the coast to Acapulco before turning to their monitoring stations off the Colombian coast.

As U.S. interdiction efforts have put increasing pressure on Colombian cocaine being smuggled in through Florida, traffickers have turned to the use of planes flying from such cities as Cali to Central Mexico, where the drug is off-loaded into vans or other vehicles for smuggling into the United States.

Carrillo Olea, whose official title is general coordinator for investigating and combatting drug traffic, estimated that two to three cocaine-carrying flights are attempted from Colombia to Mexico each week.

Last week, which he called “very fortunate,” Mexican authorities detected three such flights and seized 2.5 metric tons of cocaine base.

In a related development, it was learned that anti-drug training missions being flown by Mexicans in U.S.-supplied Cessna Citations have led to the interdiction and seizure of substantial amounts of cocaine being flown to Mexico from Colombia. One such seizure occurred earlier this month in the state of Sinaloa and involved about 350 pounds of cocaine, a U.S. official familiar with the operation said.

A U.S. drug intelligence source said that, because of the increased cooperation between Mexico and the United States, a large amount of cocaine that Colombian smugglers would have attempted to bring into Mexico now is being diverted to Guatemala. From there, smugglers are believed to be attempting to fly it into the United States or to transport it over land routes.

Officials at the Justice Department and the Customs Service drew encouragement from their meetings this week with Carrillo Olea. They said that the Mexican official is carrying out the pledge by President Carlos Salinas de Gortari to step up cooperative efforts by Mexico and the United States against illegal drug trafficking.