BOGOTA, Colombia » Colombia’s National Police director says officials have arrested four men in the slaying of a U.S. anti-drug agent.

Gen. Jose Roberto Leon says the four men are alleged members of a gang that specializes in robberies. Two are taxi drivers.

Both Colombian and U.S. officials have said they believe that Drug Enforcement Administration agent James Watson was probably killed in a common robbery, not because of his law enforcement work.

Leon says Edgar Javier Bello is believed to be the man who stabbed the 43-year-old Watson on June 20 after he left a restaurant and got into a taxi.

He said today that an informant will receive about $25,800 for information in the case.

In addition to Colombia, Watson was a DEA agent in Honolulu and San Juan, Puerto Rico. He also served three deployments to Afghanistan and was in the U.S. Marshals Service and U.S. Army before joining the DEA.