DPS troopers are on the southbound lanes of I-45 at Nursery Road, where the crash occurred sometime after 3 p.m.
We know one person has been taken to Memorial Hermann Hospital in The Woodlands in serious condition.
The extent of his or her injuries was not immediately known.
A right lane and three center lanes have been shut down as officers investigate the crash.
Drivers who travel this stretch of I-45 in Montgomery County should find alternate routes to avoid the traffic jam, as drivers slow down to see what happened.
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