Item believed to be large balloon discovered by fishermen off Alaskan coast

Fishermen have recovered what appears to be "a pretty big balloon" off the coast of Alaska, a U.S. official confirmed to CBS News Friday.

The balloon is being brought into port for examination, the official said, adding that photographs of the object are being examined, but it will not be possible to determine exactly what it is until it arrives in port.  

The official stressed that the balloon was not shot down by the U.S. military.