MILFORD, Neb. -- Three people were killed in a Tuesday morning crash on Interstate 80.

The Seward County Sheriff's Office was called to the scene of a multiple vehicle accident on I-80 near Milford around 5:45 a.m.

The preliminary investigation indicated that a tractor-trailer was traveling eastbound on I-80 and crossed the median, entering the westbound lanes of travel.

According to the sheriff's office, the tractor-trailer struck a westbound tractor-trailer head-on. An additional tractor-trailer traveling in the westbound lane swerved to avoid the collision, causing it to cross the median and overturn in the eastbound lanes of travel.

A fourth individual was life-flighted to Bryan Medical Center and is listed in critical condition.

I-80 eastbound and westbound lanes were shut down near the Milford exit Tuesday morning following the crash, re-opening after several hours.