A scene keeps flashing through Officer Omar Delgado’s mind, sneaking into his slumber every time he closes his eyes to sleep.

It is of his first look inside the Pulse nightclub. Dozens of people were motionless on the blood-soaked dance floor, and the Eatonville police officer had just burst through the club’s patio door for a rescue.

“I yelled: ‘Hey, come on, get up! Let’s go! We have cover for you. Police! We’re here,’” Officer Delgado said.

Nobody budged.

It took a moment for Officer Delgado, 44, to realize that the “signal 43” he had responded to — Orange County police code for “Rush! Officer needs help” — was not an officer down, but a massacre of civilians.

Officer Delgado, who had been working the night shift in a small town eight miles north of Orlando, was in the second wave of officers who responded after the initial shooting. He wound up spending hours inside, saving a few people and watching over the many dead.

“I thought they were playing dead so they would not get hit,” he said. “It wasn’t until I got my flashlight and scanned the room and saw so much blood from where all these bodies were lying. I looked to my left, to a guy who I guess got the worst end of it, and that’s when it hit me: ‘Wow, these people are all dead,’” Delgado told the New York Times.

He arrived at the beginning of a three-hour standoff. Officer Delgado dragged some of the wounded to safety and took cover behind a wall.