Gas gang rob Brits.
Diane Bezer and Geoff Sillito woke to find pounds 1,200 missing along with passports, bank cards, mobile phones and their sat nav.
The raiders leaked the harmless but potent gas through vents of the van as the couple slept in a layby near La Croix Valmer, southern France.
Diane, of Winterbourne Bassett, Wilts, said: "When we woke up everything was gone and we had a really woozy feeling."
French police warn thieves are increasingly using gas to rob people.