JACKSONVILLE, Fla. -- Police are investigating two fatal shootings that took place on opposite sites of Jacksonville Sunday night.

At about 9:45 p.m., shots were fired at the BP gas station at the corner of Old St. Augustine and Losco roads. One victim was transported to Shands-Jacksonville Medical Center and pronounced dead, investigators said.

Police said the shooting occurred after an argument inside the store escalated to gunfire.

Investigators have not released the name of the victim, but they said they are talking to witnesses and have identified a person of interest in the case.

"We have not been able to identify who our actual shooter is and the reason for the disturbance," Jacksonville Sheriff's Office Sgt. Daniel Janson said.

The second shooting occurred one hour later in the 4000 block of Marland Street in northwest Jacksonville.

Police officers said they arrived and found a man shot. He was transported to Shands with life-threatening injuries and died overnight.

Homicide investigators have not released the name of the victim. Detectives questioned several witnesses and said they have a person of interest in the shooting, but no arrest was made.

Police asked anyone with information in either shooting to call Crimestoppers at 866-845-TIPS. Callers can remain anonymous and be eligible for a reward of up to $1,000.

Channel 4's John Dunlap is talking with police about both shootings. This story will be updated as more information becomes available and Dunlap will have live reports on the local station beginning at 5 p.m.