Sniffer dog
The New York City police are deploying so-called Vapor Wake Detection Dogs as part of beefed up security arrangements for the US Independence Day events on the Fourth of JulyReuters

Sniffer dogs trained to detect airborne scents of explosive substances will be deployed in New York City during events during the city's Fourth of July celebrations. The so-called Vapor Wake Detection Dogs are the first of their kind, because of their ability to detect vapour trails even after a bomb carrier has left an area.

The New York City police are deploying this first class of explosive-sniffing canines as part of beefed up security measures amid growing terror threats, especially in areas with large gatherings. These specially trained dogs will be among the thousands of security personnel – including police officers and the city's new counter-terrorism squad – who will be on patrolling duties during a massive fireworks display planned over the East River as part of Independence Day events.

The Labrador Retrievers and their handlers will reportedly be deployed in undisclosed locations around the city on the Fourth of July. These canines are part of the New York Police Department's (NYPD) Critical Response Command (CRC). The pilot batch comprised eight dogs that graduated from the training programme in March, just two days after the deadly Brussels terrorist attack.

"This time last year we were just creating the CRC – the strategic response group – and beginning to acquire the Vapour Wake dogs," Police Commissioner Bill Bratton was quoted by Reuters as telling reporters on Friday. "This year they are here, fully trained, fully equipped."

According to AMK9, the company that developed the programme, Vapor Wake dogs are different from the traditional explosive detection dogs (EDDs), because they can identify odours in the air, while bomb dogs can only detect static objects. Vapor Wake dogs can sniff out scent particles produced by a person's body heat, enabling them to detect explosives being carried by an individual or a suicide bomber's explosive vests, even when they have left a place or are in motion.

Training Vapor Wake dogs take about 15 months, compared to the two-month duration required to train regular EDDs. Vapor Wake dogs are also trained to do the traditional bomb detection searches.