The Harris County Sheriff's Office said first responders rushed the brother from the 3200 block of Bolton Gardens Drive on Tuesday afternoon to the hospital in critical condition.
According to HCSO's preliminary information, the suspect showed up at about 1:30 p.m. at his 17-year-old ex-girlfriend's home in the Greenfield Village subdivision in northwest Harris County, where the girl's brother intervened and asked the 18-year-old to leave.
Then, a fight broke out between the suspect and the brother, and at some point, the suspect pulled a knife and stabbed the victim.
"Blood was just constantly coming out," Connie Medrano, who lives nearby, said.
Surveillance footage obtained only by Eyewitness News shows the victim clutching a wound in his stomach area and walking to a neighbor's house for help.
"He was holding and kind of screaming, like, 'It hurts, it hurts,'" Medrano said.
The video shows the suspect walking and then running in the opposite direction of the victim. Deputies found him at an undisclosed location. First responders also rushed him to the hospital with a minor hand injury.
"We feel sad for the mother because, as a mother myself, I can't imagine her seeing something like that happen to her son," Medrano said.
The sheriff's office didn't give the victim's age or the suspect's identity.
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