Explosive device detonated in a Sam's Club; second device found in suspect's car

An explosive device was detonated Thursday in aisle 4 of the Sam's Club in Ontario, California. No one was hurt in the incident.

Initially reported as a structure fire when a 911 caller described a "popping sound" within the store, authorities later discovered that the small explosion was intentionally set.

Witness Norman Svikss recalled the incident, saying "It wasn't like an earth-shaking big explosion. It was like a slow sound, like 'boom.' And there's no smoke, nothing. Then the employees start running around and then they slowly said, 'Hey, we have to evacuate the building,' because it's a fire or something."

After a brief chase, a male suspect was taken into custody when law enforcement detained the individual at a traffic stop three miles from the Sam's Club. Authorities searched the vehicle and found another (possibly explosive) device.

The Ontario store is about 40 miles east of Los Angeles. Following the suspect's arrest, a neighborhood in Fontana was evacuated while police had a bomb squad and SWAT team surround an apartment they believed might contain a bomb.

ATF agents were brought in to investigate what type of device was detonated in the store.