It was around 10 p.m. on June 25, 1996, when Staff Sgt. Alfredo Guerrero went to check the security post on the rooftop of an eight-story Khobar Towers apartment building at Dhahran Air Base, Saudi Arabia. He asked the sentry on watch if everything was OK.
Below them, residents in the rooms were settling in for the night. Most were with the 4404th Wing -- protectors of the "no fly zone" in Southern Iraq in support of Operation Southern Watch.
Some Airmen were writing letters or calling home. Some were playing cards or shooting pool in the recreation room. Others were showering and some were already asleep. For many, there were only a handful of days left on their tour before the "Freedom Bird" would fly them back home from their deployment.
As the two security policemen talked, Sergeant Guerrero noticed an olive drab gas truck following a white Chevy Caprice. Winding their way through the parking lot, the car came down the fence line and parked, flashing its headlights. The truck nudged its way up to the perimeter fence. A two-lane street ran between the fence and the building.
Two white-robed men wearing the traditional red and white checkered headdresses got out of the truck and ran to the car.
Sergeant Guerrero's heart jolted. The sedan peeled out and was soon out of sight.
"At that point I knew that something pretty big was about to happen," Sergeant Guerrero said.
In a split second, he radioed the control center about what was happening. As he called for an evacuation of the apartment building, his sentry was on it, running for the rooftop door. A second sentry, who had been guarding the other side of the building, followed suit.
Fists pounding doors and scuffling boots echoed down the corridor of the eighth floor.
"We need to evacuate! Get out now!" the sentries yelled.
The doors crashed open and a growing group of Airmen scuttled down the stairwell to the seventh floor.
In the apartment building next door, an Airman lay down to sleep. He pulled a scratchy Army blanket over his head to keep out the meat-locker cold of his air-conditioned room.
"Just two more weeks and I'll be home," then Staff Sgt. Bob Oldham thought to himself, his eyes getting heavy.
Then there was a massive boom. The explosion rocked Sergeant Oldham's room and he froze. He thought the floors were collapsing as the intense sounds reverberated through the apartment complex.
The blast blew away the whole face of Bldg. 131. The explosion's massive force twisted Sergeant Guerrero around. He checked himself to see if he was still alive.
"Everything went pitch black -- I couldn't see anything, couldn't hear anything," Sergeant Guerrero said. As the dust settled, "I was looking at the lights of downtown Dhahran," from where seconds before a concrete wall had stood.
All around him was wreckage. The wounds on his face didn't faze him as he pulled bits of furniture and masonry off an Airman who a minute ago had been right behind him helping with the evacuation. Pulling the Airman to his feet, he put his arm around his shoulder and led him down the seven flights of stairs.
Sergeant Oldham sat up in bed and went to get up.
"Ow!" he said as a shard of glass dug into his barefoot heel. "I decided it was time to grab some shoes and my dog tags and get the hell out of there," said the former active-duty supply troop.
Outside, those who could helped the wounded and tended to the dead. The sergeant witnessed the rows upon rows of seriously wounded and bleeding. He attributes organization and everyone's will "to keep it together" as a key factor in minimizing the death toll.
"Self-aid and buddy care, an annual training, is what saved the victims. It'll save your life and that's the bottom line. You'd be surprised what comes back to you -- how to apply bandages, splint an arm, treating for shock," said Sergeant Oldham, now a master sergeant with the Arkansas Air National Guard.
After the tragedy, with three hours still left on his shift, Sergeant Guerrero went back to his post and continued his vigilant watch.
"People were looking at me like I was a ghost or something," he said.
"As cops, we do this kind of stuff all of the time, and 99 percent of the time nothing ever comes of it," Sergeant Guerrero said. "Eventually it's going to count. That's why motivation and practice -- doing what you're supposed to do -- is so important."
Then on July 3, 1996 -- while still deployed in Saudi Arabia -- Sergeant Guerrero received the Purple Heart Medal and Airman's Medal for his heroic actions from then Air Force Chief of Staff Gen. Ronald R. Fogleman.
Security forces troops who come across him today know the sergeant is the hero who they've studied about in their career development course books and training.