ST. LOUIS COUNTY • Microphones that alert police to the sound of gunfire will be added to the Castle Point area of St. Louis County, as the technology moves beyond the city of St. Louis.

The St. Louis County Council voted Tuesday to authorize County Executive Steve Stenger to accept a Justice Department grant of up to $400,636 that would, in part, acquire a Shotspotter system.

It will be used in the area near Halls Ferry and Chambers roads, with a range of two or three miles, according to Officer Benjamin Granda, spokesperson for county police. The plan is to start operation in the spring.

He called it an “additional resource to help us keep the community as well as officers safe,” adding, “It’s been proven successfully throughout the country.”

He said the area was chosen to provide “the best crime reduction and community engagement” for the investment. He noted, “It is one of the areas our department focuses on with hot-spot policing initiatives.”

According to Granda, at least $300,000 of the grant will be used for the technology, and at least $100,000 for community counseling and violence de-escalation in areas most affected by gunfire.