The New York Police Department is equipping its bomb-sniffing canines with an upgraded electronic harness that can sense biological and radiological threats that go unnoticed by the dogs.

Police officials say the dogs will patrol the city’s subway system — an area frequently targeted by terrorists.

The new technology, called “Transit Enhanced Detection Dog,” or TREDD, equips regular explosive detection K-9s with a wearable harness replete with sensors that detect a variety of threats, including explosive, biological, chemical or radiological weapons. The device then sends the readings to a mobile command post in real time.

Lieutenant John Pappas, commander of Transit Bureau K9 in Queens, came up with the idea for the device after receiving intelligence that terrorist organizations were looking to bypass the city’s security systems.

“What I found in the intelligence … is that international terror organizations like al Qaeda, ISIS and many others were intentionally creating a gap in our detection capability specific to the dog,” Pappas told Fox News. “They were kind of gearing it to avoid detection by a dog.”

Pappas explained that terrorists were building explosive devices that dogs were not trained to detect.

“They were starting to create unconventional explosive devices, things that they knew — because they study us — that these dogs cannot detect. Normal explosives like TNT and C-4 and dynamite, they know that these dogs can detect. So they went a different route.”

With the help of grant money, Pappas and the NYPD partnered with Massachusetts-based private technology company Blueforce Development Corporation to address the new threat.

Following the creation of the harness in 2015, the NYPD and FDNY began training their first responders to understand the harness’ readings and to test the capabilities of the device.

Readings are sent from the device to a mobile command post in real time, which allows NYPD officers on the ground to detect threats that would otherwise be imperceptible.

Command post officers can also see where the dogs are at all times.

“I can stay in one location. I can track them all over,” NYPD Officer and trainer Edwin Ramirez said. “So if we have a team that’s in Brooklyn or a team that was sent to Manhattan, I can pull them up and see where they are at the same time — without being on scene — and get all the readings and information from them.”

Pappas said TREDD dogs were first used during the pope’s visit and the United Nations General Assembly in 2015. More recently, the technology was deployed during the April 12 Brooklyn subway shooting, when the NYPD initially responded to reports of several undetonated explosive devices in subway stations before determining the reports were unfounded.

“We had these units deployed there, and I knew exactly where they are. I knew exactly what they were detecting, and I would move my pieces around to make sure that I’ve covered all the areas that needed to be swept,” Pappas said.

For the NYPD and other departments around the country, COVID lockdowns afforded more time to revamp their K-9 units.

“During the pandemic, when everybody was locked down, it was an opportunity to finally fine-tune it and upgrade the technology,” Pappas explained.

“I can honestly say that our team, the NYPD K9 program, came out of the lockdown much stronger than when we went into it because we had time to train. We had time to upgrade our equipment, fine-tune it and kind of finalize this version of it to put it out there,” he continued.

The NYPD also shared the tech with the Pentagon, giving them the option to upgrade their K-9 capabilities.

“It does us no good to hoard this when there’s a threat like this up against all of us. This isn’t just a threat to New York City,” the K9 unit trainer said.