SAN DIEGO -- Authorities announced the arrests Tuesday of two men and a woman suspected of kidnapping and robbing more than two dozen migrant workers in North County communities over the last several months.

Kevin Anderson of Vista and Escondido residents Nicole Couch and Thomas Malcolm Graham were taken into custody during two separate traffic stops Monday and Tuesday, according to sheriff's officials.

Since at least June, Anderson and Graham, both 22, and Couch, 25, allegedly have approached immigrant day laborers awaiting jobs and offered them employment.

The suspects would then allegedly drive one, two or three of them at a time to a remote location and rob them of cash and valuables at knifepoint.

One of the roughly 30 victims of the holdups, which occurred in rural sections of Encinitas, Escondido, Fallbrook, San Diego, San Marcos and Vista, suffered a minor stab wound, authorities said.

Investigators believe others have been victimized in the robbery series and urge them to report the crimes by calling the Vista Sheriff's Station at 760-940-4571.

The immigration status of anyone who comes forward will not be questioned, officials said.