It's a rental ambulance, from the rental company "Ciné-Autos", which changes the plates as the shoots progress (sometimes to respect a spatio-temporal framework).
https://www.cineautos.com/#prettyPhoto[674]/0/
Photo taken on the set of "Otages" (2009).
https://www.cineautos.com/#prettyPhoto[674]/4/
http://www.imcdb.org/vehicle_1544214-Renault-Master-2000.html