The accident is on the northbound lanes of Highway 59 at the West Loop.
Authorities say a U-Haul that was pulling a car and a Honda Pilot collided on the highway.
Firefighters pulled out two people from the wreck Pilot and then used the Jaws of Life to free another two people who were stuck inside.
All four were transported to nearby hospitals via ambulances. Their conditions were not immediately available.
The exit ramp to the West Loop from the inbound lanes of the Southwest Freeway was completely shut down, causing a massive backup on the highway.
No other details were immediately available.
Stay with Eyewitness News for the latest details.
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