Humpback whales spotted feeding in Boston Harbor

BOSTON — People taking whale watch cruises out of Boston usually have to travel miles out to sea to spot whales.

But several humpback whales have been spotted in the harbor in the last few days, providing thrills just a quarter mile from downtown Boston.

The Massachusetts Department of Conservation and Recreation posted a video on Twitter of a whale breaching, calling it a "beautiful and rare sight to see."

The presence of whales in the busy harbor also comes with a warning. The Coast Guard is urging mariners to use "extreme caution" and keep a safe distance from whales.

A spokeswoman for Boston Harbor Cruises, which offers whale-watching cruises, said company naturalists have identified five to six individual whales.

Experts say they will stick around as long as there is food.