The electronics panel on a Metro rail car was left open to the public Friday afternoon, according to a Metro rider.

The open panel was spotted and photographed on a 4000-series rail car on the Red Line around 1:30 p.m. by rider Christopher Burger as he traveled from Union Station to Farragut North.

He said he worried the open door could have become a security threat or safety hazard due to the sensitive electronic equipment inside.

Burger credited Metro with responding quickly when he reported the issue, though. Within two stops of him contacting the train operator, he said, two mechanics came aboard and began fixing it.

It is not immediately clear what controls are housed in the electronics panel to understand what hazards may have existed on the train.

"It's not intended to be open, and we certainly appreciate the concern," Metro spokesman Dan Stessel said.

He noted the problem did not cause any Red Line delays or reported issues.

Metro has had several problems this year with riders reporting train doors opening while trains are running. At least one rider was even able to photograph the open doors, leading to disciplining of the train operator. Open car doors present an obvious safety concern as riders could fall from moving trains.