HEBBRONVILLE, Texas (CBSDFW.COM/AP) — Authorities say two small helicopters collided while herding deer on a ranch in South Texas Wednesday morning, killing two men.

Texas Department of Public Safety Sgt. Nathan Brandley said two Robinson R22 helicopters struck in midair Oct. 23, near Hebbronville — a community about 160 miles south of San Antonio.

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Brandley says one helicopter was able to land and the other crashed after the collision, killing both people on board. One was pronounced dead at the scene and the other was pronounced dead at a hospital.

He said one of the two people in the other helicopter was injured.

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The cause of the crash is not known at this time, nor are the identities of those involved.

The Federal Aviation Administration and the National Transportation Safety Board are investigating.

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