The ads are enticing: “Instant cash for your used phones.” So enticing, in fact, that D.C. Police Chief Cathy L. Lanier believes that they will encourage theft by giving criminals a quick and easy way to sell stolen phones.

Lanier took to the airwaves Thursday for her monthly “Ask the Chief” segment on WTOP radio (103.5 FM) to announce her “new crusade” against a new kind of mall kiosk, one where cellphone owners — or thieves — can receive up to $250 for a device in working order.

There are six such kiosks, called ecoATMS, within 25 miles of the District, Lanier said.

“This is a problem for me,” she said. The kiosks are “not a good system. I’m sure it’s increasing the problem” of theft.

Faced with a wave of cellphone thefts at the onset of 2012, which leveled off by the end of the year, Lanier became a leading advocate of pushing the wireless industry to honor requests by owners of stolen phones to disable the devices remotely and permanently. Rendering the phones useless makes them worthless on the black market. But Lanier’s newer concern is not founded, said Ryan Kuder, director of marketing for the California-based company that operates the ecoATMs.

The company handles thousands of transactions a day at 300 kiosks across the country, and there are inquiries about the possibility of theft in only one in 5,000 sales, Kuder said.

In the D.C. suburbs, he said three or four stolen phones have shown up in the past six months, and all were returned to their owners.

“Obviously we’re disappointed,” Kuder said. “We do a lot of work to make ecoATMs an unattractive place to get rid of a stolen phone.”

Customers are required to provide valid ID, leave a thumbprint and have their pictures taken before making an exchange, which is done much like a bank machine transaction, Kuder said. The phones are held 14 to 30 days, depending on local laws, to give time for police reports to be completed and investigated. Records of all transactions are available to police on demand.

Kuder said kiosk security cannot immediately determine whether the person selling the phone is the actual owner, but he said his company is working with cellphone companies to get access to serial numbers to do just that. For now, the information is stored and can be used later to identify a potential thief. He said the photo, ID and thumbprint are significant deterrents to criminals.

“We’re fully aware of the fact that theft of cellphones is a problem nationwide,” said Kuder, whose company has a section on its Web site called “Notice to law enforcement” to address concerns. “We have tried to make our kiosks a very bad place for thieves to go.”

Recycling cellphones for profit is not new, according an industry trade group called the CTIA-The Wireless Association. But the idea of exchanges at kiosks appears to be a new concept, said John Walls, an association vice president.

Established ways of getting rid of old phones include returning them to wireless companies. Some, such as Verizon, donate the phones to programs that give free phones to victims of domestic violence, to help them in emergencies.

Representatives of police agencies in Howard and Prince George’s counties, D.C. area jurisdictions where ecoATMs are located, said their chiefs had not heard of theft surges linked to the machines, which are typically placed in suburban shopping malls. The company said it has no immediate plans to put one in the District.

Lanier, who did not respond to requests for an interview, has made other efforts to combat thefts and robberies involving cellphones, which at times have been violent.

Lanier said on the radio that she has been in touch with company representatives, and she described them as cooperative and the talks as encouraging. She did not detail what was discussed.

Lanier said on the radio program that because the company recycles the phones, the information would not be checked against the national database of stolen phones.

Kuder, the ecoATM marketing director, said that is not entirely true. He said 60 percent of the phones are returned to the market, which means that when resold, they would be checked against the database. The rest, he said, are mostly old-style flip phones and are sold to recycling plants and melted down for the materials.