An eye-popping 6,755 postal employees were attacked by dogs in 2016, according to statistics released Thursday by the United States Postal Service. That's an increase of more than 200 since 2015. The numbers were released along with advice for pet owners—keep dogs shut in a different room before opening the door for a delivery person, don't take mail directly from a delivery person while dogs are watching—ahead of National Dog Bite Prevention Week. These were the top 10 cities for dog attacks on postal employees last year: