Marine experts have lifted a stranded whale from London's Thames River onto a barge in hopes of transporting it back out to sea.

The northern bottle-nosed whale, about six meters in length, appeared in the river Friday.  It became stranded overnight near the Albert Bridge, upstream from the Houses of Parliament.  Rescue teams caution that the animal has been injured and still might have to be given a lethal injection.

This northern bottle-nose is a deep-diving species, native to the Arctic and the northern Atlantic, and is considered highly intelligent and curious.

Londoners crowded the banks of the Thames to watch the rescue efforts.

Officials say this is the first whale seen that far upriver since records were kept, beginning in 1913.

Some information for this report was provided by AP.