James Johnson, 23, has been charged with aggravated assault with serious bodily injury.
Investigators say Precinct 4 constables were called to the scene at the La Escencia apartment complex on North Vista Drive near the North Freeway around 8:30 p.m. Wednesday.
Authorities say Johnson had been in an argument with a 22-year-old woman and her brother.
According to witnesses, Johnson pulled out a pistol and pointed it at her.
Constables were in the process of filing charges against Johnson for that incident when they were called back to the scene just hours later at 12:09 a.m.
Investigators say Johnson shot at the 42-year-old woman's car as she drove away from the complex. Her 22-year-old daughter and 4 grandchildren were inside the vehicle at the time.
The older woman was shot in the head. She was taken to Houston Northwest Hospital, where she is in critical condition. The daughter and grandchildren were not injured.
Resident James Drake told ABC13 he heard the shots and then ran into action.
"All I hear was, 'That's my mom, that's my mom.' So I went over there and all I see was a gun shot through the head," Drake said.
Drake was on the phone with a dispatcher, trying to save the victim's life.
"Called 911, told them where we were at, and he told me to get a cloth towel to put over the wound, put pressure on it, so I did," he explained.
The 911 dispatcher told Drake to count the victim's breaths. "She was still alive. She was still breathing. She was not saying anything. She was just unconscious," Drake recalled.
Eddie Gonzalez was outside his apartment as the bullets were flying.
"I hit the ground. That's my instinct these days," Gonzalez said.
Residents are surprised even more people were not injured.
"Not even 20 feet from my door. You know, the window is right here, so I am lucky that no bullets went through the house," Drake said.
Authorities are still looking for Johnson. If you have any information about where he may be, you're urged to call the Harris County Sheriff's Office Violent Crime Unit at 713-274-9210.
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