Global sting began by creating message service for crooks

Acting U.S Attorney Randy Grossman, right, speaks as law enforcement officials look on during a news conference announcing Operation Trojan shield Tuesday in San Diego. (AP Photo/Denis Poroy)

SAN DIEGO — When the FBI dismantled an encrypted messaging service based in Canada in 2018, agents noticed users moving to other networks. Instead of following their tracks to rivals, investigators decided on a new tactic: creating their own service.