A new active shooter detection system could revolutionize the way law enforcement handles active shooter scenarios.

The new system was demonstrated this week at a grammar school in Methuen, Mass., the Associated Press reported:

Smoke alarm-sized sensors installed in classrooms, hallways and other points throughout the building were activated by the sounds of gunfire, and police officers were immediately able to track his movements and quickly subdue him.

… The new system was installed at no cost by Shooter Detection Systems, a Massachusetts-based company. Company CEO Christian Connors said it is installing the technology in two more schools in Virginia and California, as well as undisclosed airports.

Founded in 2013, the company is among others across the country trying to market such “active shooter” systems to the owners and operators of malls, airports, government offices, schools and other public buildings.

“It’s amazing, the short, split-second amount of time from identification of the shot to transmission of the message,” U.S. Rep. Niki Tsongas, who was on hand at the demonstration, told the Associated Press. “It changes the whole game. Without that shot detection system, we wouldn’t know what was going on in the school … Valuable, valuable time can be lost. Unfortunately, with school crisis situations, it’s about mitigating loss.”