Bolts Falling Out

[Jak]

Doing a quick visual inspection this weekend, checking oil and water etc, and was horrified to find a couple of bolts sitting on top of the engine. After a look around found that these had come out of where the air intake from the radiator bolts onto the side of the engine. 6 had come out - 2 sitting on top of the engine - a further 2 were loose.

The car was serviced 1000 miles - 6 weeks ago.

Is this a case of not putting them back properly or do they suffer from vibration loosening them up?

I am looking for a bit of advice before I ring the dealer.

[Jak]

Thanks - found another bolt on the engine after a closer look - Will keep an eye on them.