The worker was stopped and detained at the entrance of the Palo Verde Nuclear Generating Station, said U.S. Nuclear Regulatory Commission spokesman Victor Dricks. Security officials then put the nuclear station on lockdown, prohibiting anyone from entering or leaving the facility.

Authorities described the device as a small capped pipe that contained suspicious residue.

Capt. Paul Chagolla with the Maricopa County Sheriff's Office said sheriff's officials rendered the device safe and that investigators were interviewing the worker.

"Our Security personnel acted cautiously and appropriately, demonstrating that our security process and procedures work as designed," said Randy Edington, the chief nuclear officer for plant operator Arizona Public Service Co., in a statement.

The incident was considered an "unusual event"—the lowest of four emergencies the plant can declare, said Jim Melfi, an inspector with the U.S. Nuclear Regulatory Commission.

 Source : AP / Breitbart News