Bees attack. Again!

This is the 3rd time my company being "attack" by wild bees. The first time, the company end up paying Rentokial (how to spell?) to destroy the colony. The 2nd time, the bees stay for few days then flew away. This time, it has been a week these bees building their hive.... and ladies and gents, today I was lucky to have a camera with me, and this is what I caught..

Up close and personal

Any one have any idea how to get rid of these bees??