The crash occurred just before 11 a.m. on eastbound I-84 near milepost 51 in Ada County, Idaho, according to police.
Five vehicles were reportedly involved in the crash, which police say resulted in a fatality and other serious injuries.
The eastbound lanes of I-84 were blocked for approximately four hours, but all lanes have since reopened, according to police.
The crash remains under investigation by Idaho State Police.
This is a developing story. ABC4 will update this post with more information as it becomes available.