FRESNO (AP/CBS13) — A New Year’s Day head-on crash killed seven children and two adults along a central California Highway, and now the National Transporation Safety Board is joining the investigation.

The NTSB said Tuesday it will work with the California Highway Patrol in the investigation of the crash involving two pickup trucks on State Route 33, but its staff will not travel to the site.

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The seven children and a woman were in a Ford F-150 that burst into flames when it was struck by a Dodge pickup driven by a man, who was also killed.

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The CHP has said evidence at the scene indicated the Dodge veered onto the road shoulder and then swerved back
.
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The crash site was between the towns of Avenal and Coalinga in an agricultural area about 50 miles (80 kilometers) southwest of Fresno.

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Copyright 2020 CBS Broadcasting Inc. All Rights Reserved. The Associated Press contributed to this report.