BATON ROUGE - The WBRZ Investigative Unit learned the Federal Aviation Administration’s air traffic control tower was unmanned at the time a BRPD helicopter with two officers went down Sunday morning, killing them.

WBRZ has learned that the FAA staffs BTR’s airport control tower. Employees work there for 19 hours a day, but between the hours of midnight and 5 a.m., no one is in the tower.

Flight data shows the BRPD chopper took off around 2:26 am and crashed at 2:38am. It was in the air for 12 minutes. During that window, it appears no one was tracking the flight from the control tower.

The crashed helicopter was found sometime before noon on Sunday— at least eight hours after it went down. A retired FAA crash investigator said this is not unusual.

"A helicopter like that on patrol and flying low, you don't have to be talking to anyone or on someone's radar, it depends where you are at," John Abel a former FAA crash investigator said. "If you are near Baton Rouge, you may be on radar. If you are in their airspace they will know you are there. If you are out over a cotton field and down low, they aren't going to know you are there unless you talk to them."

The officers were in pursuit of a suspect, according to sources.

The helicopter crashed behind Norris Cummings' house. He said it was one of the loudest bangs he's ever heard in his life.

"I heard a car pass first on 190 zooming," Cummings said. "I know it was going 100 miles per hour. Helicopter came across, within a minute, I heard the boom."

A preliminary report sent to the FAA indicates the tail hit a tree, causing the helicopter to land upside down. It's not yet clear if there were any other issues that led to the crash.

BRPD identified the officers as Sgt. David Poirrier, 47, and Cpl. Scotty Canezaro, 38.

Autopsies are pending for both men. Because they died in an air crash, the FAA is sending a special autopsy kit to the coroner's office which will have to be used as part of the investigation. Those kits are supposed to arrive sometime Tuesday, the West Baton Rouge Coroner’s Office said.