Middlesex County OPP are asking motorists to stay off the roads unless travel is absolutely necessary.
A winter storm moving through the area has brought high winds, snow and pockets of very poor visibility.
OPP say while investigating a car that went into the centre median on the eastbound 402 near Centre Road a cruiser was struck by a passing motorist.
A tow truck assisting the motorist had its lights on, as well as the emergency lights on the cruiser were activated. A second OPP cruiser arrived with its emergency lights on and flares were set up behind it.
Police say the original collision was minor and once that vehicle was cleared out of the way a second vehicle hit the rear of the cruiser causing serious damage. The officer involved was treated for minor injuries.
The two drivers that hit the OPP cruiser have been charged with Careless driving contrary to section 130 of the Highway Traffic Act.