Last January, two men arrived in Chester from out of town. It was just before 8 p.m., and they were ready to sell their green 1996 Kawasaki motorcycle.
The pair had advertised the vehicle on Craigslist. The potential buyers had arranged the meeting. On Worrell Street, the groups met and $1,200 changed hands.
But later that night, after driving a couple of hours to return home, the sellers realized the 12 $100 bills were counterfeit. They'd been robbed.
Chester Police Chief James Nolan IV recently recalled that case as the jumping-off point for a yearlong effort to focus on similar crimes. Police began tracking "online robberies" in their own category, separate from other robberies.
In the last year, police departments across the country — from Palm Beach, Fla., to El Paso, Texas, to Indianapolis — have taken steps to curb an increasing number of robberies that originate on apps like OfferUp. In Indianapolis, a man recently died after being shot last month during a transaction that began online.
Since January 2017, Chester police have logged 28 online robberies, in which the victim was a buyer or seller, according to police data.
"It's a trap. You know the person is going to show up, and you know they're going to have money," Nolan said. "It's almost like a better version of the pizza-delivery robberies."
The number of these robberies marks a significant increase from previous years' estimates, said Capt. James Chubb, who maintains the data as head of the detective division. He could not specify just how steep an increase, since the department didn't track these crimes separately before last year.
Of the 28 online robberies, 25 involved a weapon. In several of those cases, Nolan said, the victim was shot and injured.
Police just served a search warrant in a December case in which a man was held up, robbed of money and personal belongings, and shot, Chubb said. He declined to provide more details since police are still investigating and have yet to make an arrest.
Nolan said police have seen victims come from as far away as Lancaster to buy or sell items, sometimes in the middle of the night. Many don't know much about Chester, a city that is among the country's most dangerous. Last year, Chester's homicide rate per 100,000 people was more than that of any other U.S. city, according to an Inquirer and Daily News analysis.
"It's easy pickings. An unsuspecting person comes in," Nolan said. "They're expecting just to make a business transaction, and a predator is waiting on them."
Most of the Chester online robberies originated on OfferUp, an up-and-coming mobile app
– similar to Craigslist and eBay — where users can quickly arrange to purchase items, such as dirt bikes, iPhones, and other electronics. Others began as transactions on Facebook's Market Place or on Letgo, another buying-and-selling app.
The investigative process usually involves obtaining search warrants for electronic communications, and then for physical property. In some cases, including that motorcycle theft last year, officers set up an undercover operation to buy back stolen items and then make an arrest.
"The headache for us on these cases is that they are very laborious," Nolan said. "You've got a lot of man-hours, a lot of search warrants."
In other areas across the region, such as Camden and Upper Darby, police departments have seen success after designating secure locations, often called safe zones, for online transactions. The safe zones are under 24/7 surveillance, which serves as a deterrent for criminals, police said.
"We got on top of it pretty early," said Capt. Richard Verticelli of the Camden County Police Department, which set up an online transaction safe zone in Camden several years ago. "It really has worked well for us."
Upper Darby and Camden police said they started the safe zones after noticing an increasing problem with people getting ripped off — or worse — by strangers they met online.
"Just the pure lack of common sense on the part of the victim is beyond my comprehension," said Superintendent Mike Chitwood of the Upper Darby police, which has a safe zone outside the station.
"Some people are just generally naive," Nolan said.
"If you don't know an area, don't say, 'Oh, yeah, I'll go meet you there,' " Chubb added.
Spokespeople for OfferUp and Craigslist could not be reached for comment. But on OfferUp's website, the company says it does not tolerate illegal activity.
"The overwhelming majority of Craigslist users are trustworthy and well-meaning," reads a statement on Craiglist's site. "With billions of human interactions, the incidence of violent crime related to Craigslist is extremely low."
Both OfferUp and Craigslist also offer safety tips for users.
Nolan said Chester is working to establish best practices for investigating these crimes before focusing on preventive measures, which could include establishing a safe zone of their own.
For now, though, Nolan and Chubb can offer advice.
If you're meeting to buy or sell, do it in a public place during business hours, they said, and avoid middle-of-the-night meetings in places with which you aren't familiar.
"If somebody moves the meeting," Nolan said, "that's a clue."
Chubb said, "Just use a little bit of common sense."