A gunman engaged the two troopers around 12:45 p.m. in Mifflintown Borough, exchanging shots with both troopers, PSP said.
After a search, the trooper was found in Walker Township around 3 p.m.
The gunman and one trooper died while the other trooper was hospitalized with serious injuries, police said.
Gov. Josh Shapiro and PSP Col. Christopher Paris were at the hospital with the wounded trooper.
This is a developing story. Check back for details.
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