Not much can be done.
A car with a full gas tank, a propane cylinder and a cell phone detonator is a bomb on wheels and can go anywhere completely unnoticed until it’s detonated.
And we are dealing with people who believe that when they detonate the vehicle and blow themselves to smithereens, if they take some of us Infidels out they will be rewarded with virgins in paradise. They MUST be gotten rid of.