FORT HOOD — Two Army warrant officers and two sergeants first class died in Monday’s Black Hawk helicopter crash at Fort Hood, officials said Friday.

The soldiers were all from Fort Hood’s First Army Division West, which released their names.

They were: 40-year-old Sgt. 1st Class Toby A. Childers, originally from Hays; 40-year-old Chief Warrant Officer 3 Stephen B. Cooley, originally from Cantonment, Fla.; Sgt. 1st Class Jason M. Smith, 35, a Destrehan, La., native; and 40-year-old Chief Warrant Officer 2 Michael F. Tharp, originally from Katy, Texas, a city near Houston.

According to alumni records, Childers was a 1993 graduate of Hays High School.

The Black Hawk crash occurred sometime after 5:49 p.m. Monday in the northeast portion of the Fort Hood training area. A Division West spokesman said photos and Army career backgrounds on the soldiers were not released Friday “out of respect to the families.”

First Army Division West is an active-duty unit that trains many National Guard and Reserve units before they deploy.

All four crew members were assigned to the division’s 2nd Battalion, 291st Aviation Regiment, First Army Division West. The aircraft, assigned to the 7th Battalion, 158th Aviation Regiment, was on a routine training mission, officials said.

The cause of the crash at this time is unknown, pending an investigation by a team from the Army Combat Readiness Center, headquartered at Fort Rucker, Ala., officials said.

That three-member team arrived at Fort Hood in the days following the crash, and the investigation could take weeks or months.

“Investigations do not have an assigned duration. We will not speculate on an estimated completion date,” Michael Negard, a spokesman for the Combat Readiness Center, said Wednesday.

He said such investigations consist of two phases — the field investigation and the completion of the technical report.

“The field investigation includes the exploitation of the actual crash site, extensive data collection and analysis followed by investigation board deliberations,” Negard said. “The field investigation results in an interim determination of accident cause and appropriate recommendations. The technical report is completed by gathering all the technical reports supporting the investigation, completing the written report and finalizing the findings and recommendations.”

Friends and others were remembering the deceased soldiers on social media Friday.

“God Bless you Toby Childers ... you were an awesome soldier, fellow aircrew member, and wonderful person ... you will be greatly missed,” Lori Russell posted on Facebook.

Shannon McManigal Sauter posted: “I’m heartbroken for these families. Praying for them all.”

The last deadly Fort Hood Black Hawk crash happened Nov. 29, 2004, when the helicopter went down approximately 30 miles northeast of Fort Hood on its way to an Army depot in Texarkana.

According to Killeen Daily Herald reports from that investigation, released nearly three months after the crash, it was determined the helicopter hit “stabilizing cables for a TV tower while flying in foggy conditions,” and the crash was ruled “pilot error.”