‘Gruver Bomber’ arrested after months of explosions rock Palmer Township

PALMER TOWNSHIP, Pa. — A 57-year-old man who was already facing weapons and drug charges has been arrested in connection with months of mysterious explosions that have rattled windows and disturbed residents throughout Palmer Township.

Ronald Erney of Fogelsville was taken into custody Friday after Palmer Township Police dubbed him the “Gruver Bomber” and executed a search warrant at his Upper Macungie Township residence.

For months, Palmer residents had reported late-night window-rattling explosions throughout the township. The Palmer Township Police Department’s Criminal Investigation Division used investigative methods and tips from the public to identify Erney as a suspect.

In May 2024, Erney was arrested by the Pennsylvania Attorney General’s Office on serious drug and weapons charges, including felony counts of manufacturing controlled substances, illegal firearm possession and weapons of mass destruction.

According to The Morning Call, investigators found 800 grams of suspected methamphetamine, nearly 800 fentanyl pills, cocaine, 13 firearms and explosive device components at his home.

After spending three months in Lehigh County Jail, he was released in August 2024 after posting $25,000 cash (10% of his $250,000 bail).

Friday’s search required evacuating several neighbors until Erney’s residence was deemed safe. Inside, detectives discovered numerous chemical substances used to make explosives, along with fuses, cardboard tubing, PVC tubing and projectiles.

They also found 10 firearms and tools to construct “ghost” guns—weapons the convicted felon was prohibited from possessing.

Erney now faces seven counts each of possession of explosive materials and disorderly conduct in Northampton County related to the Palmer explosions.

Additional charges in Lehigh County include weapons of mass destruction and 10 counts of illegal firearm possession.

He was arraigned and committed to Northampton County Prison with bail set at $50,000. A preliminary hearing is scheduled for Sept. 26.