Authorities say two pickup trucks were involved in a wreck just before 3 a.m. and pulled over to the shoulder.
A man who got out of his vehicle to check on them was then hit by another driver and thrown into traffic. Officials say he was hit by more drivers, including a Harris County Sheriff's deputy in his marked vehicle.
The victim died.
I-45 fatal crash
A driver in a red Jeep traveling northbound on the feeder road hit the chunk of concrete barrier that landed on the road from the initial crash. That person was not injured.
The concrete was blocking one of the northbound service road lanes just before West Road.
Officers shut down the mainlanes of the freeway for nearly five hours as they worked to clear the wreck.
Police say the DWI Task Force will be checking drivers to see if any of them were intoxicated.
Officials warn that being on the freeway after a crash is dangerous.
"Anytime you're involved in an accident on the freeway, if the vehicles will move, get off the freeway as soon as possible. It can be deadly," said HPD Lt. Larry Crowson.
The cause of the collision is under investigation.
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