Police responded to the 1200 block of East Lynwood Drive around 8:30 p.m. following reports of shots fired.
Upon arrival, officers found James Eddie Merkson, 30, of San Bernardino suffering from gunshot wounds in the apartment's courtyard area. Merkson was transported to Loma Linda University Medical Center but shortly succumbed to his injuries.
The shooter was last seen getting into a car and fleeing. Investigators believe the two men had been involved in an argument.
The investigation is ongoing. Anyone with information regarding the incident was urged to contact Detective Al Tello at (909) 984-5747 or Sergeant Gary Robertson at (909) 841-5361.