Saying it is one of the risks of using online classified advertising, New Orleans police are searching for a man who they said claimed to be selling a car on Craigslist but instead robbed a would-be buyer at gunpoint last week.

The alleged robbery happened about 6:20 p.m. Friday in Algiers.

Police said the victim spoke to a man who said his name was “Angelo” and who agreed to meet the victim in the 2900 block of Hudson Place to test-drive a Volkswagen Passat that Angelo had posted as for sale on the online classified site.

A short time after the two started the test drive, Angelo pulled out a gun.

“You know what time it is,” he told the victim, police said.

The 42-year-old victim handed over $3,500 in cash he had brought with him to buy the car and was let out of the vehicle at the same place the test drive began. Angelo then drove away in the 2006 Passat.

Cmdr. Shaun Ferguson, who oversees the New Orleans Police Department’s Algiers district, said the would-be seller did not have any connection to the Hudson Place block where he and the victim met, and the phone number listed in the ad for the car appears to have been disconnected.

Detectives are trying to pull information from the Web posting that can help identify the unknown robber, Ferguson said.

He described the robber as a “well spoken” black man with a light complexion in his late 20s or early 30s, about 5-foot-9, with diamond studs in each ear.

Friday’s robbery is not the first of its kind that detectives in Algiers have investigated.

On March 29, a man was robbed when he met someone who had posted an online ad for a laptop computer.

In both instances, Ferguson said, the victims were from out of town and might not have been familiar with the residential neighborhoods where they were meeting the supposed sellers.

“The message we want to put out is they should pick a highly populated place that is well lit” if making a night transaction, Ferguson said.

Detectives do not believe the two cases are related.

Ferguson said a robber could be behind any ad posted online by an anonymous seller. “Craigslist is a good tool, but it’s one of the risks,” he said.

Anyone with information about the robberies is asked to contact 4th District detectives at (504) 658-6040 or Crimestoppers at (504) 822-1111.

Follow Danny Monteverde on Twitter, @DCMonteverde.