WACO (AP) — All lanes of Interstate 35 through Waco have reopened following a fiery chain collision involving four semitrailer rigs and two passenger vehicles that killed three people.

Waco police Sgt. W. Patrick Swanton says the northbound lanes reopened about midnight. The southbound lanes opened a couple of hours after the Tuesday afternoon wreck.

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Authorities say a semitrailer and two cars were slowing when another semi slammed into the cars from behind with all erupting in explosions and flames.

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Witnesses reported seeing two people trying to crawl from the wreckage when explosions engulfed them before they reached safety.

Swanton says a connector route to northbound I-35 will remain closed because of structural damage from the incident.

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