Oklahoma helicopter crash leaves 3 dead, medical crew members identified: Everything we know

Three members of a medical air transport crew died late Saturday night when their helicopter crashed in western Oklahoma.

Here's everything we know so far about the crash and the investigation.

What happened in Oklahoma medical helicopter crash

Saturday night, an Air Evac crew had dropped off a patient at Mercy Hospital in Oklahoma before heading back to its base in Weatherford.

At 11:23 p.m., the operations control center for Air Evac Lifeteam lost contact with the helicopter, a Bell 206L-3, according to a social media post by Air Evac Lifeteam.

The three crew members aboard died in the crash. On Monday, Air Evac Lifeteam identified the crew members as pilot Russell Haslam, flight nurse Adam Tebben, and medic Steven Fitzgerald.

"Please continue to hold all of their families in your hearts," the team said in a Facebook post. "Russell, Adam and Steven, we miss you so much. We’ll take it from here."

More: Medical helicopter crash leaves three dead Saturday night near Hydro, Oklahoma

Medical helicopter crash near Weatherford, Oklahoma

According to flight tracking data, the helicopter lost contact outside of Hydro, Oklahoma, a town 8 miles east of Weatherford.

When will the investigation be complete?

Air Evac Lifeteam has turned over the investigation to the National Transportation Safety Board.

While the board will release a preliminary report, the investigation could take 12 to 24 months to complete.

This article originally appeared on Oklahoman: Helicopter crash near Weatherford, Oklahoma: Everything we know