Unfortunately there is almost nothing that can be done ot even attempt to contain any secondary fires that may start as the result of these exploding flaming cylinders until the main fire begins to burn itself out. You cannot even water bomb one of these fires as the sudden quenching of any remaining pressurized cylinders will cause them to explode into small fragmented shrapnel with up to a 1000 times the force of a regular hand grenade. That would be for all heated cylinders not just ones which were flammable. Foam or dry chemical will do nothing since the fire has its own source of oxygen. If you cold somehow blast enough CO2 to freeze the fire the same thing would happen as with water.
The best thing to do is to keep everyone 500 feet or more away from the fire until all threat of exploding cylinders has passed then move in and put it out.
That patrol officer was dumb and lucky dumb for driving past the already stopped vehicles to assess the situation. Surely he was able to see the cylinders exploding and becoming un-guided missiles long before he drove that close.
Lucky in that one of them didn't impale his vehicle before he cold back away.