At about 1:30 a.m., officials responded to a multi-car pileup that included "20 to 30 vehicles," according to the Austin Police Department.
KXAN-TV reported the collision took place in the southbound lanes of State Highway 130 near Harold Green Road and officials believe heavy fog and low visibility were factors in what led to the crash.
Austin-Travis County EMS evaluated 56 people, transported nine and were refused by one person. Two of the people transported sustained serious but non-life threatening injuries.
Fog and smoke from fireworks created dangerous road conditions in the Houston area as well.