Luis Diaz, 20, is in critical condition having been shot behind the left ear. The shooter is still on the run.
The shooting happened just after 11pm Sunday on South Post Oak near Orem in southwest Houston.
When officers arrived, they found Diaz in his Dodge Charger. Diaz's friend was a passenger in the vehicle and was not injured.
The Charger had crashed into another vehicle at the intersection. The shooter's vehicle, a white boxy vehicle, possibly a Toyota Scion, was not at the scene.
"If anyone saw or heard anything, please come forward," Laura Marin, Diaz's cousin, told Eyewitness News. "We want to find out, try to find the person who needs to answer for what happened."
Another cousin, Aida Diaz, spoke to the passenger about the shooting.
"What my cousin did was move over to try to pass and when he passed that's when the other car sped up next to him and took out a gun and pointed the gun at them," said Diaz. "All of a sudden, he heard one shot. He put his head down and another shot came and he saw my cousin injured. He tried to grab the wheel."
Diaz, a Bellaire High School graduate, arrived home Sunday afternoon for a two-week leave for a wedding, according to his family. He's an Army Specialist stationed in Germany.
HPD says it is looking to review surveillance video from nearby businesses in hopes of finding anything that could lead them to the suspect or suspects in the case.
Diaz's family wants justice for him, a soldier who found Houston more dangerous then active duty overseas.
"He's there to serve our country and then he gets here and this happens," said Diaz.