The drug-smuggling network in the United States has unintentionally provided some government officials in Colombia and Mexico with private airplanes.

Colombian officials currently control 120 U.S.-registered airplanes that were confiscated from drug traffickers and Mexico has another 400, according to several aviation insurance groups.

The insurance groups say they don't care if the foreign governments keep airplanes that were owned by drug smugglers, but they say most of the planes were stolen and should be returned.

In testimony before a Senate committee, the insurance groups urged Congress to pressure the State Department either to enforce a rather fuzzy 1937 treaty with Mexico or toughen language in a new one being drafted to get a handle on the problem in that country.

In 1937, Mexico promised to return any vehicle or aircraft that was stolen, but the temptation of owning an airplane has proved too much for some, the insurance groups claim. Among the examples cited was a case in which a Mexican official used a stolen Cessna 402 for two years after it confiscated, returning it only after it broke down.

Another incident involved a Piper Seneca that Mexican officials used for five years. At one point, a Mexican official promised to return the airplane in exchange for money. When the U.S. owners refused, the airplane was sent back in a variety of unusable pieces.