The Texas Rangers joined the investigation into an officer involved shooting in Ennis Saturday night.
In a press release, Lt. Mike Hopson of the Ennis Police Department said officers responded to a report of a man being threatened with a gun around 6:45 p.m.
Officers found the alleged gunman in his car and tried to stop him. But they said the person would not comply with their commands and drove toward the officers.
One officer fired through the windshield of the car, striking the man. The officer was not hurt.
Paramedics transported the man to Baylor Medical Center in Dallas. The man's name has not been released but Ennis police said he is is critical condition.
The department said officers recovered a loaded bolt action rifle from the gunman's vehicle.
The man faces charges of aggravated assault on a police officer, attempted capital murder and deadly conduct.
The officer who fired on the man is on adminstrative leave.