SAN DIEGO -- Law enforcement officials in San Diego and Riverside counties are working to find out who is responsible for the kidnapping of a trucker last Saturday morning.

The California Highway Patrol said a truck driver pulled over near the intersection of northbound Interstate 805 and Interstate 15 at 5 a.m. Four armed men took the driver and his truck and headed north to Mira Loma in Riverside County, the CHP said.

Many truckers said there is camaraderie out on the road, so when a Chevy Astro van pulled up behind Marcus Williams last Saturday and flashed its lights he thought it was someone trying to help, trying to alert him that something was wrong.

Trucker Daniel Bell said Williams should have kept going.

"I'll wait 'til I get to a rest area. I'll wait 'til I get to an area where there's people around, then I'll check," said Bell.

The CHP said any driver should do that if someone is trying to get them to pull over.

"If they're ever flagged down by an individual or somebody attempts to stop their vehicle that they drive to the nearest well traveled location if they can," said CHP Officer Mark Gregg.

10News talked to several truck drivers in National City, and one driver who has been on the road for more than 40 years said, "I think it was an inside job. Reason being, who else is gonna know what's in a trailer? These trailers, when they leave outta here, they're locked, they're sealed, nobody knows what's going on in those trailers."

Some drivers said truck heists happen more often than many think.

"It happens on the freeway. It happens at … people park on the onramps, on bridges; it's happened there, so it's not that uncommon," said Bell.

"You just gotta watch what you're doing out here. Some of these people are crazy. I mean, they're flat crazy," said the veteran truck driver.

The group involved in Saturday's heist got away with about $500,000 worth of electronic equipment, the CHP said.

The truck's driver was not injured in the incident.