reporter: a rare sight in france, flashing police lights and sirens on the chanson lycÉe.it has sparked an internal investigation. make are not here to amends. we are here to express our unhappiness. a week and a half ago, four were in an ambush in southern paris. were set on fire while the officers inside were prevented from getting out. with onebadly burned, going to intensive care. it's just another sign of a badly overstretched force struggling to cope in an increasingly dangerous environment. >> it's getting more and more violent, more and more often. clearlyople who are trying to kill cops. we just want to do our jobs the .ight way in good conditions >> it's not the first time officers have demanded increased resources. parasol the largest protest since 1983. >> we feel we've been forgotten by france after being its heroes. there are lots of nice words that are touching and that we appreciate, but there has been little action. >> police have worked even harder, working more overtime to maintain security. the government has been recently former president nicolas sarko