Boston College law professor Kent Greenfield stands in front of the BC law offices in Newton, Mass. Friday. Greenfield was active in creating a group of law schools that brought a suit challenging a decade-old federal law requiring universities to give military recruiters the same access to students as other recruiters. The U.S. 3rd Circuit Court of Appeals recently ruled in their favor, and invalidated the law. (AP Photo/Winslow Townson)

Associated Press Writer

PARIS — French police on Sunday ended their practice of hiding plastic explosives in air passengers’ luggage to train bomb-sniffing dogs after one such bag got lost, possibly ending up on a flight out of Paris’ Charles de Gaulle airport.

The luggage that police used Friday for the exercise has not turned up yet.

Three flights that arrived in Los Angeles and New York were searched, but the luggage in question was not found.

No passenger has contacted French authorities to report discovering a bag with nearly 5 ounces of explosives tucked into his or her suitcase.

Police say there was no chance the explosives could go off since they were not connected to detonators.

Still, Prime Minister Jean-Pierre Raffarin was critical of the mistake.

‘‘The fight against terrorism and insecurity is a priority for the government,’’ a statement by his office said. ‘‘But (Raffarin) made clear his concern in the face of the way the training for explosives searches was conducted at Roissy Charles de Gaulle.’’

Raffarin said the procedure was ‘‘susceptible to making the relevant passenger run a risk in the eyes of foreign authorities when arriving in the destination country.’’

Police soon after announced they had ordered a stop.

‘‘The procedures that were used Friday night will no longer be allowed,’’ said Pierre Bouquin, a spokesman for France’s police force, known as gendarmes, who conducted the training.

‘‘We’re going to stop practicing this on the bags of travelers’’ in all of France, he said.

Airport police deliberately placed the plastic explosives into a passenger’s luggage early Friday evening, Bouquin said.

The luggage was lost on a conveyor belt carrying bags through a restricted area from check-in to planes.

The explosives could have made it onto one of up to 90 flights leaving Charles de Gaulle airport. Police did not know the bag’s destination and quickly alerted the relevant airlines.

No one saw the bag go on a plane, but ‘‘there is a very strong chance that it left’’ on one, Bouquin said.

Two police officers faced disciplinary action because of the somewhat embarrassing incident, Bouquin said.