Raleigh, N.C. — Federal investigators have joined the pursuit of a locksmith operation that uses deceptive practices to take advantage of people locked out of their homes and vehicles.

WRAL News exposed the operation three months ago in a hidden-camera investigation, prompting a flood of complaints to the state Attorney General's Office. Attorney General Roy Cooper then filed suit against three companies that each operate under numerous names in an effort to shut down the operation and win some money back for consumers.

Cooper said Wednesday that federal authorities have recently become involved because some shady locksmith operations cover several states and because of questions about the immigration status of some contractors.

Despite all of the attention, the operation continues to prey on area residents.

Tanner Triplett, 19, of Holly Springs, said he became a victim when he locked his keys in his car.

When he called his mother, Gena Triplett, for help, she searched Google.com for local locksmiths and passed several names and phone numbers to him.

"I called the cheapest one, one that said $29," Tanner Triplett said.

It was SOS Locksmith, the same company profiled in the April 23 WRAL News investigation. Hidden cameras showed the company promising to get a Cary woman back in her house for a $35 fee, but after the two-man crew drilled out both of her front door locks, they tried to charge her more than $400 for the service.

After Tanner Triplett called the company, a man in an unmarked Dodge Charger showed up and opened the locked car door within minutes. The man handed Triplett a hand-written receipt reading "26 Hours Locksmith" and charging him $137 instead of the promised $29 fee.

"I was surprised, but I felt like I had to do it," Triplett said.

"This was a total rip-off. A total scam, fraud, whatever you want to call it," Gena Triplett said. "It's a life lesson."

Cooper said stopping predatory locksmiths isn't easy because they hide in various shell companies and use bogus addresses.

In the Tripletts' case, SOS Locksmith provided an address on Pinewood Drive in Apex as its office address. The address is actually a private residence.

"We're going to keep pursuing these companies, take them to court, and run them out of North Carolina," Cooper said. "We want consumers to let us know if they've been ripped off."

He urged consumers who call locksmiths for help to make sure the person who shows up displays a North Carolina locksmith license and that the company has a verifiable business address. Most legitimate locksmiths also use marked vehicles and wear uniforms.