Anyone know what this animal could be?

Early morn...the local birds all very angry together... Screeching ...At something moving around, fast...in the trees.
I thought at first ..."large squirrel", big enough to bend thin branches by its weight. But it was a very dark colour..clearly not one of the local red squirrels. I couldnt see its shape..but As I watched...it came closer, stopping for a while in my plum tree, I guessed that's why all the plums disappear so fast...When close enough to see body and tail...I thought

yikes! What is it.!!??..As big as a cat..with a catty style face..with some markings a bit like a dark tabby...but no cat could ever swing around in trees like this chap. Spreading his arms from branch to branch, a bit ape like...and so fast along any thin branch..leaping to another one as each one bent. Still concealed by lots of leaves, but I saw a thick tail as long as its body. I searched images for something to match...this one looks closest...but it can't be right..!!. Unless an escapee...no zoos nearby...

http://blog.ctnews.com/dennis/files/2010/12/fisher3.jpg

Anyone know what it could be? This is river side woodland, in Brittany.

It's a marten! They are lovely, sweet and in addition to being very playful they will gnaw everything they can get at, including any accessible car cables….

Definitely swinging and leaping..very much like squirrels do...and the last of my quetsches disappeared as I watched! What a nerve!

I will get up earlier tomorrow...and have my camera ready....thanks to both of you!

Michael and Sandy...you two seem to be both right.. Thank you!!!

Perhaps there's a crossbreed!

I looked at a lot more images...never seen either of those two before, but both like to be 'near water'...both about the same size and habit...

The 'tabby cat' impression...seems to be closer to a genette...but photos of both, vary from animal to animal...and its impossible to be sure...until I get the chance to see the animal again..both fruit eaters...that explains a lot! Some of my figs had big bite marks...before the whole lot vanished..in one night...along with a stack of little yellow plums..

They don't seem to be enthusiastic about pears or apples, so far.....and one plum tree close to the house..survived the raids.

Im thrilled to bits...I understand they are both... very ordinary, but if they are to be regular visitors to my mini garden (an island)..its such a treat.. to watch them! And the wild life multiplies...if you don't mind sharing food..!

Google 'pine marten' ... will take all your fruit and robbed our cherry tree of every single cherry overnight. Could possibly be that. Not sure about the swinging action from tree to tree but looks similar to your image ...

It sounds like a Common Genet (Genetta Genetta), quite common in the s/w of france, we have some in the trees near the river which runs though our land.

Google the name and let me know what you think.