GALVESTON (KTRK) --Like many families, Galveston was a place to relax, enjoy the weather and celebrate the Fourth of July holiday.
Robert and his wife were leaving the island Monday night after a weekend of fun. He was driving near the local shopping center, which is a common area for bicyclists to ride.
Jhoanna Santos, the manager at a nearby clothing store, says she's seen many close calls before.
"If they don't see them and they are driving and they aren't very careful. It's very dangerous," Santos said.
The couple saw the driver of a truck strike a bicyclist. The orange police lines still mark where he was dragged through the parking lot.
"He just hit him, the truck went right into him and the guy hit the ground and hit his head. He came up holding his head," said the good Samaritan.
The driver never stopped.
Robert's wife jumped out to help with an EMT and nurse already nearby. Robert chased after the driver, calling 911 and directing Galveston police exactly where to go.
"You all need to get a police car out here to take my spot. There's no telling what he's capable of, he just ran over a guy and left him," he told the dispatcher.
Police arrested 28-year-old Defain Mendez Aguilar. He's now charged with leaving an accident involving bodily injuries.
"The guy got out of the car with his hands up," Robert said.
The good Samaritan says what was even more difficult to believe was Aguilar had his wife and children inside.
"The kids both said they told him to stop after he hit the guy and I said well we got the right guy," said Robert.
"You're showing your kids, I just hit a guy, it's OK, just take off," Santos added.
"I think we need more people like that. If I'd been around I'd done the exact same thing," cyclist Steve Covington said.
The victim was taken to UTMB. His name and condition have not yet been released.