An Atlanta police officer was hit by a truck Tuesday night in an incident at the Atlanta Medical Center parking deck.

Atlanta police spokesman Officer John Chafee said that around 7:45 p.m., officers learned of a dispute inside the hospital lobby, and as they were responding, they were told that a perpetrator fled into the parking deck, and that he may have been carrying a gun.

As officers entered the parking deck, they were advised that the perpetrator was possibly in a red truck, Chafee said. They found the truck on one of the deck’s higher levels, and when they tried to stop it, it backed up and drove at the officers, nearly striking one.

“As it came down one of the ramps, it actually struck a second officer, and at some point during that incident, the officer discharged his firearm at least one time. It appears that he struck the vehicle, breaking out one of the windows on it,” Chafee said.

The vehicle, described as a red pickup with dark-tinted windows and a male driver, fled the scene. The officer who had been struck sustained a hand injury but was treated on the scene and was alert and in stable condition Tuesday night, Chafee said.

Authorities are still investigating the details surrounding the dispute. Chafee said investigators do not yet know if it involved hospital patients, visitors or any other parties, and they do not know what led to the altercation.

“A lot of the people that were involved left the scene afterwards, so we’re still trying to locate people and figure out exactly what was going on,” he said.