It happened in a home on the 6900 block of Stansbury Lane in Landover around 9:30 p.m., Prince George’s County Police said.
Officers found three wounded from gunfire and pronounced the man and girl dead at the scene.
The woman was taken to a nearby hospital with serious injuries.
Detectives don’t believe the crime to be random, adding that there is no ongoing threat to the community. Anyone with information is asked to submit a tip using the P3 Tips app or call PG Crime Solvers at 1-866-411-TIPS.
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