Yonkers Police Department's K-9 School has resumed operations, with several new K-9s beginning the department's rigorous certification school this week. 

The school will run for the next few months, after which the K-9s and handlers will hit the streets as full-fledged K-9 units. 

Part of their training involves tracking scents in the environment they will be working in – the city's streets and trails. 

The police department advises residents not to be alarmed if they see the K-9s in their neighborhoods, as they are in class. 

They also remind people not to pet the K-9s during this time, as the dogs need full concentration to pass the school.