One person in the SUV survived.
The Chihuahua state prosecutor's office said the group was driving from Dallas before dawn yesterday to visit family in Mexico. The accident happened at a bridge near Ojinaga, a border town across the Rio Grande from Presidio, Texas.
Officials say the driver realized too late that the bridge didn't span the Conchos River, and the vehicle fell upside down into the water.
A spokesman for the state prosecutor's office says there were no signs or barriers keeping traffic off the bridge.