STARR COUNTY, Texas (ValleyCentral) — A National Guard helicopter crashed near La Grulla Friday afternoon, killing three people, authorities said.

A news release from Fort Bliss, located in El Paso, says the UH-72 Lakota helicopter was assigned to the federal Southwest border support mission when it crashed just before 4 p.m.

The release says three National Guard soldiers and a Border Patrol agent were aboard when it crashed. Two soldiers and the agent were killed. The other soldier is in critical condition at a McAllen hospital.

The names of the deceased have not been released until the next of kin have been notified.

The cause of the accident is under investigation.

Texas Department of Public Safety South Texas Regional Director Victor Escalon said the helicopter was not part of Operation Lone Star, Governor Greg Abbott’s border security initiative to secure the border.

The Starr County Sheriff’s Office stated it is assisting with the downed helicopter, which is on the east side of the county.

Valley Central’s Brian Svendsen said Texas Division of Emergency Management, DPS and Texas Game Wardens have also been at the scene, which is two miles east of La Grulla.

He said already a number of vehicles arrived pulling portable light towers operated by generators.

Starr County Judge Eloy Vera told Border Report the chopper came down in a rural area.

“It did go down. It was a clean field so we don’t know what could have caused it. But its under investigation,” Vera said.

This is a developing story and will be updated as more information becomes available.