Say 'drivers', not 'cars': it's the people in inside the boxes that do the stuff

This is the Mirror we're talking about. I very much doubt any of its readership would be able to tell the difference between correct wording and a hilarious version with the bus seemingly having a mind of its own and trying to kill its driver.

/Christine

Grammatically, the 'leaving' clause doesn't necessarily pick up the bus. It's vague and can be interpreted in the way you choose, but the usage of this sort of phrase is generally '..., which incident caused this or that to happen'. The writer won't have had it in mind to specifically implicate the bus.