Feb. 19 (UPI) — One person was killed and five wounded in a shooting involving two groups at an Indianapolis Waffle House early Monday, authorities said.

Just after midnight, the two groups got into a confrontation inside and outside of the west side Waffle House and shots were fired. It was not clear how many of those shot were part of the initial confrontation or if they were customers, police said.

An adult female died from her wounds at an Indianapolis-area hospital. Ambulances transported four people — three men and a woman — to local hospitals, as well.

Authorities learned a fourth person was taken by a private vehicle to the Indiana University Health Methodist Hospital.

“The incident started with a disturbance between two groups that escalated to gunfire,” the Indianapolis Metropolitan Police Department said, according to ABC News. “It is not clear at this point if any of the people injured were also individuals who fired shots.

“That will be part of what detectives will attempt to determine. Detectives are also working to review any video surveillance footage that may be available as the business did have surveillance cameras.”

Police said officers are looking for additional witnesses who were at the popular 24-hour restaurant at the time of the shooting.