Three people were killed and one person was injured in a helicopter crash near the U.S.-Mexico border Friday evening, Joint Task Force North said in a statement.

       The copter was National Guard Lakota UH-72, according to a defense official.

       The helicopter assigned to the federal Southwest border support mission crashed at approximately 2:50 p.m. MST Friday while conducting aviation operations near Rio Grande City, Texas, JTF-N said. The cause of the accident is under investigation.

       Texas's Dept. of Public Safety was also assisting with the investigation.

       This is a developing story. Please check back for updates.