This photograph of a Washington State police officer holding a fraction of a car part led to the arrest of a driver in a fatal hit-and-run. Source @WASTATEPATROLHoping to solve a fatal hit-and-run case, Washington State Police turned to social media for help and subsequently transformed a Reddit user into an amateur detective.

Initially, officers shared an image on Twitter of an unidentified object recovered from the scene of a hit and run where a cyclist was fatally struck by an unidentified black vehicle.

However, the police had little success in identifying the part until the image was posted on Reddit. Shared in a sub-Reddit called “What Is This Thing,” a section devoted to identifying the obscure, a Reddit user with the username /u/JeffNuts was quick to identify the part.

Explaining that he was once a Maryland State vehicle inspector that was well versed in car headlight inspections, the Reddit user identified the metal piece as belonging to a section of a “Chevy Silverado headlamp bezel."

This week, Washington State Police trooper Johanna Batiste posted to Twitter that "detectives made an arrest" after "Reddit users [identified] a photographed broken car part."