BELEN, N.M. -- Authorities said they have arrested a former North Charleston police officer after finding a cache of explosives and chemicals at a home.

The Valencia County, N.M., Sheriff's Department received an anonymous tip over the weekend that directed deputies to a mobile home just south of Belen.

The homeowner was put under surveillance and investigators served a search warrant at the property on Tuesday evening.

Authorities said Joe McFarlin, 62, is a former explosives ordinance disposal expert with the Navy. They said McFarlin is not being investigated as a terrorist, but has been charged with possession of explosive devices, which is a felony in New Mexico.

Investigators said they found at least 20 pounds of binary explosives that can be used to make small improvised explosive devices, along with blasting caps, electric and hand detonators and unidentified explosives.

McFarlin worked as a patrol officer for the North Charleston Police Department from 1997 to 2001, said Spencer Pryor, public information officer for the department.