A Boston police officer opened fire on a dog outside the Boston Public Library on Thursday morning, officials say. At 9:22 a.m., officers responded to a call at the Boston Public Library, located at 700 Boylston St., according to a statement from the Boston Police Department.

The dog was eventually found in the Boston Common/ Downtown Crossing area where officers were eventually able to tase the dog, finally subduing it.

A "vicious dog" evaded police officers near the Boston Marathon​ finish line on Thursday, prompting an officer to fire their gun.