On July 22, Lehigh County District Attorney Gavin P. Holihan announced two men being charged in connection to an incident in Catasauqua involving an explosive device being thrown from a moving vehicle will face all charges in Lehigh County Court of Common Pleas after a preliminary hearing.

Catasauqua residents Jack Pletz, 24, and Matthew David Pletz, 57, are charged with felony counts of conspiracy to commit weapons of mass destruction, unlawful possession or manufacture and conspiracy to commit risking a catastrophe; and misdemeanor charges of conspiracy to carry explosives on conveyances, as well as conspiracy to make offensive weapons and conspiracy to possession of prohibited offensive weapons.

Magisterial District Judge Todd Heffelfinger ordered all charges against both defendants be held for court.

Matthew Pletz remains in Lehigh County Jail on $50,000 bail.

Additional charges were filed July 22 against Jack Pletz that include possession of a firearm prohibited and possession of a firearm with an altered serial number.

The father and son are both charged in the incident that occurred the morning of May 19, near Salem United Church of Christ, 615 Third St. It occurred on Election Day, and, at the time of the explosion, the church was being used as a polling location.

Pennsylvania State Police determined the explosive device had been detonated about half a block from the polling entrance. No information exists to cause investigators to believe this incident was related to the polling location. Residents who vote at that polling place were still able to cast their ballots at the church.

As PSP was investigating the explosion, investigators found a 12-gauge shotgun with no serial number inside the Pletz home, and additional related shotgun ammunition was found in Jack Pletz’s bedroom. A fingerprint found on the shotgun was identified as belonging to Jack Pletz, Holihan said.

As of July 22, Jack Pletz had been taken into custody but not yet been arraigned on these new charges.

On May 19, PSP troopers were called to the area of the church for reports of an explosive device that had been detonated. First responders found remnants of an explosive device at the intersection of Walnut and Third streets. The explosive device was determined to be a red tubular cardboard fragment with melted red end caps and was consistent with a “M-type” explosive device.

Investigators found video surveillance from a nearby location that showed a green 1998 Chevrolet pickup truck traveling north on Third Street toward the intersection of Walnut Street. The truck driver was identified as Jack Pletz.

Shortly after the truck stopped at the intersection, the engine revved and the truck continued north. Just after 9:10 a.m., a loud explosion was heard in the area where the truck was driving. The pickup truck was then located stopping at the home where both Jack and Matthew Pletz lived in the 200 block of Pine Street, less than a block from where the explosion occurred.

The investigation revealed Matthew Pletz was seated inside the passenger area of the truck at the time of the explosion.

Several witnesses identified the men inside the truck as Jack and Matthew Pletz, according to Holihan. Police also interviewed the driver of a vehicle who passed in the area just seconds after the explosion.

A search warrant was obtained, and investigators found 18 homemade illegal M-type explosive devices and one plastic-encased explosive device filler inside the pickup truck.

This case is being investigated by Troopers Ryan Ziegler and Matthew Brennan and will be prosecuted by Chief Deputy District Attorney Sara A. Moyer.