The incident happened in the 6100 block of Glemont Drive just before 10 p.m.
According to the Houston Police Department, a witness noticed the suspects approach the 54-year-old man sitting on the sidewalk.
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HPD said it is possible that the suspects were waiting for the man because the second teen, the car's driver, was waiting in a blue Honda Accord.
At one point, the man tried to run away from the suspect, who brandished a pistol at him. HPD said the man was unable to run fast enough to escape the suspect, who caught up to him.
The witness told police the suspect, who gave chase, knocked the man down and was yelling for him to give them his wallet before hitting the victim several times with the pistol, HPD said.
Lt. Willkens said at one point that a gunshot was fired in the air. Officials said it is unclear whether it was accidental or whether they were trying to scare the man. The suspect then got into the waiting blue car and fled the scene.
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HPD said the man's injuries were severe, but he is expected to live. HPD confirmed that the man's wallet was intact when emergency personnel responded and took him to the hospital for treatment.
John Lopez, who said he witnessed the assault's aftermath, said while crime happens in the area, he's never seen anything like this.
"When I went out, I saw him sitting there; he looked sort of dazed. I actually thought he might have been in a car accident, because he looked slumped over right there. People were already helping him out, though," Lopez said.
Officials urge anyone with information on this case to call Houston police.
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