OKLAHOMA CITY (KFOR) - Investigators say they are looking into a suspicious fire at a northwest Oklahoma City apartment complex Tuesday morning. "Never did that in my life,” witness Nathan Phillips said. “Ever had a fire just go up like that." PREVIOUS COVERAGE: Firefighters knock down apartment fire in NW Oklahoma City That fire left behind charred remains at the Lakeside Village Apartments near Northwest Expressway and Wilshire. Nathan Phillips was staying with his girlfriend at the complex and he said he heard a fire alarm going off in the area. "I get closer, I see flames,” Phillips said. Battalion Chief Andrew McCann with the Oklahoma City Fire Department said when they got on scene, smoke and flames were filling a breezeway there. "The fire was contained strictly to the stairway. There was no extension into any of the apartments. All four apartments were vacant. We've had no occupants that were displaced,” McCann said. "The stairway was on fire like pretty good,” neighbor George Norwood said. LOCAL NEWS: Police: Man steals from gas station, sprays clerk with pepper spray Norwood was sitting outside at the time. He and Phillips called 911 at about the same time. "It was a little small fire and it just got bigger,” Phillips said. “I was going to put a little thing on it, but it just escalated and I was like 'oh, I can't put it out' so I just backed out." Phillips also said he knocked on some nearby neighbors' doors to let them know what was going on. Luckily, no firefighters or residents were hurt and no one was displaced. Right now, the fire is under investigation and is considered suspicious with investigators chasing down leads.