WILLINGBORO — A 20-year-old man has been charged with the murder of a 21-year-old woman who was found dead in her car last month.

Marvin A. Coleman Jr. was arrested Tuesday afternoon after a traffic stop near his home.

The body of Maribely Lopez, of Lindenwold, was found on Medley Lane in the Millbrook Park section of the township on March 7.

The woman had agreed to meet Coleman to sell him her used cell phone, which was not stolen. A motive for the killing remains under investigation.

Burlington County Prosecutor Scott Coffina said arriving officers found Lopez in the driver’s seat of her Ford Focus with the engine still running.

The shooting likely happened around 11 p.m. the night before, Coffina said.

Coleman had made arrangements on March 6 through the marketplace app, OfferUp, to purchase a used cell phone from the victim, according to police.

An autopsy performed by Burlington County Medical Examiner  revealed that Lopez died from a single gunshot to the head.

Lopez had agreed on the app to meet Coleman in front of a vacant house on Medley Lane, Coffina said.

But instead of buying the phone as planned, Coleman executed Lopez by firing a shot through her partially opened driver’s side window. The phone that was advertised for sale was discovered by investigators still inside the car.

“People selling items online to strangers should exercise appropriate caution, such as utilizing safe transaction zones that many of our local police departments maintain in the parking lots of their stations,” Coffina said.

In addition to murder, Coleman was charged with possession of a weapon for an unlawful purpose and unlawful possession of a weapon.​

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