Trooper Martin F. Mack III, 33, and Trooper Branden T. Sisca, 29, were trying to get a man, who was walking on the highway, into their patrol car when they were fatally struck near milepost 18 just before 1 a.m., Pennsylvania State Police said. All three were thrown into the northbound lanes.
The offending driver remained at the scene, and it was unclear whether charges had been filed against her.
The civilian has not yet been identified publicly.
Meanwhile, tributes poured in for the departed troopers, one of whom also doubled as a fire chief with Trappe Fire Company in Montgomery County.
"It is with great sadness and heavy hearts that Trappe Fire Company No.1 announces the passing of Fire Chief Branden Sisca. Chief Sisca was tragically killed in a motor vehicle crash earlier today while working as a Pennsylvania State Police trooper," the department announced on Facebook.
"Right now we ask that you give his family and the family at Trappe Fire Company time to process the loss of an incredible person. Keep all of them in your thoughts and prayers." the statement continues.
He leaves behind a wife and unborn child, the department added.
Funeral services are pending.
I-95 reopened around 9 a.m.
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