One appliance and crew from Broughton and one from Newport Pagnell attended, along with an officer.
One man and one woman, injured, were out of the vehicles and in the care of South Central Ambulance Service, when they arrived.
The firefighters hydraulic rescue equipment and small gear to release a second mana and a second woman. They were both passed into the care of the ambulance service.
H5, Portway was closed to traffic while they worked at the scene.
The incident was left in the hands of Thames Valley Police.
