Thomas Kaiser, of South Plainfield, and his son, Erich Kaiser, of Monmouth Junction, were trying to set off a signal cannon a July Fourth party in Manville Saturday, July 6 around 8:15 p.m., when things went horribly awry, Manville's Deputy Chief Craig Jeremiah said.
The device exploded after being lit, sending shrapnel throughout the neighborhood, according to Jeremiah.
A party guest was suffered serious injuries to his lower torso and was airlifted to a New Brunswick Trauma Hospital, Manville police said. Several homes and vehicles were also damaged by the explosion.
Footage of the incident, which was initially believed to have been caused by makeshift fireworks, was shared by NJ Advance Media on YouTube.
Both Kaisers were charged with fourth-degree aggravated assault, possession of an explosive device, and criminal mischief. They were released pending a first appearance in Somerset County Superior Court.
The investigation is continuing. Anyone with information is asked to contact The Manville Police Department at (908) 725-1900 or the Manville Police Tips Line at (908) 725-1900 Ext. 3 to provide information anonymously. Information can also be provided through the Stopit app.
Click here to follow Daily Voice Lyndhurst and receive free news updates.