New Jersey State Police say the massive response that followed an incident on I-78 Saturday in which a trooper's windshield was shattered by an unknown projectile was done to maintain the safety of the public and the officers involved.

A Honda Civic damaged in an accident on I-78 (NJ State Police via Instagram)

Although police cannot say exactly how many police units responded to the scene, they did confirm that at least one state police helicopter was dispatched along with a K-9 unit and several troopers.

"We really never quantify that but there was at least a handful of cars that responded," Capt. Stephen Jones, director of communications for the NJ State Police told NJ 101.5 Tuesday. Callers to New Jersey 101.5 reported seeing dozens of vehicles.

Jones said a search of the area by police dogs and a helicopter "didn't turn up anybody suspicious."

The incident, which also resulted in a lockdown at a nearby school in Hunterdon County, began as an investigation into a single-car crash. While troopers were attending to the crash involving a 2000 Honda Civic driven by Antonio Melendez, Jr., 29, of Phillipsburg, the rear window of a marked State Police Chevrolet Tahoe was “struck and shattered by an unknown object,” State Police said.

As police investigated what was initially thought to be a possible gunshot, portions of the interstate were closed, causing extensive delays that lasted for much of the day.

In addition, police investigators conducted a "thorough forensic examination" to try and determine what struck and shattered the trooper's windshield. Police also collected information from the surrounding area, but the summary was inconclusive, Jones said. There was no evidence of the vehicle having been struck by gunfire or an attack on a trooper, so authorities still aren't clear on what, exactly hit the vehicle. Jones said authorities believe it may have been a rock kicked up by passing traffic.

"When you're faced with something that seems like something that can impact public safety, you have to act with caution,” Jones said regarding the the scope of the investigation.

The NJSP spokesman said the primary concern was protecting the public and the officers involved. Jones said under the circumstances, he believes the massive response was appropriate.

Toniann Antonelli is the digital managing editor for news at NJ 101.5. Reach her at, or on Twitter @ToniRadio1015.