Officers with the Allentown Police Department's Vice and Intelligence Unit raided a home on the 600 block of North 6th Street around 1:30 p.m., officials said in a statement.
Investigators seized "suspected quantities" of fentanyl and cocaine from the house, in addition to a loaded gun, they added.
Ernesto Orta, the 57-year-old who lives at the property, was arrested and charged with drug and illegal firearm possession, police said.
State court records show Orta was previously charged with retail theft.
Police acknowledged that the warrant was served as part of an ongoing investigation but declined to describe the operation in detail.
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