Help identifying bee type thing

I know this is going to be frustrating because I don't have any pics, but something flew in the window at work the other day which I hadn't seen before.

Because I sit by the window it was up to me to pick it up and put it outside again, but I've never seen anything like it.

At first I thought it was a bumble bee, because it was the same size and hairy. On closer inspection the top bit of it had a red splodge and everything else was black and the bottom half of its body was black and pointed, more like a wasp than a bumble bee.

When I picked it up in a cloth it got VERY angry, unlike any of the bumble bees I've picked up to put outside.

Does anyone have any idea what it is, it's really bugging me

 

I've Googled and managed to find a red tailed bumble bee which is apparently more aggressive. Maybe it's that and I got the red/black bits upside down cos I only saw it briefly?

Hope it's not nesting anywhere near that window because last time I got stung (by a wasp) I had an allergic reaction and my lower arm was swollen and painful for weeks afterwards.

I had a wasps nest in my flat roof last year and lost count of the number of wasps I had to rescue from windowsills. They were quite happy to let me pick them up and put them outside with my hand. The only time I got stung is when I used my dressing gown to put one outside (had to catch it in something as it was buzzing around the light), but hadn't realised the poor wasp had got stuck in the fabric and stung me when I brushed my arm against it, which is when I had the reaction.

 

Wood wasp perhaps?

http://www.wildaboutbritain.co.uk/forums/insects-and-invertebrates/27806-giant-wood-wasp.html

 

I had a Wasp Byke in our conifer hedge many years ago.We had an old neighbour who said to my wife," I will get rid of that".Unfortunately i was at work.
She poured petrol from a can, onto the nest,Ignited the nest with a match, poured some petrol on a rag,threw the rag onto the nest, then ran into her house.
It certainly got rid the nest,and half of my BL***Y hedge. Not Recommended.