A trooper working a traffic stop was “seriously injured” by a hit-and-run driver on the Mass Pike Tuesday morning, according to police. The trooper is expected to face a “very difficult recovery,” said Mass State Police Col.

A Massachusetts State Police trooper was seriously hurt in a hit-and-run crash on the Mass Pike early Tuesday morning.

The trooper was working a motor vehicle stop on Interstate 90 west near Exit 51 shortly after 2:20 a.m. when the officer was struck.