Alert: Dangerous Intersection Ahead

Google Inc.’s Waze Mobile unit is adding a new function to its interactive smartphone navigation application that alerts motorists about intersections with high crash and injury rates.

The new feature initially covers five U.S. cities: Boston, Los Angeles, New York, San Francisco and Washington, D.C. Drivers are reminded to “drive carefully” as they approach intersections with high incident rates in these areas.

Google purchased Waze, an Israeli startup formerly known as Freemap, in 2013. In addition to basic navigation functions, the Waze system also allows users to share real-time information about traffic congestion, accidents, police speed traps and other location-based updates.

Waze also works with a community of online editors to update local maps. The company is based at Google’s headquarters in Mountain View, Calif.