A three-vehicle crash in the westbound lanes of Highway 401 west of Wellington Road slowed traffic on Wednesday morning.
Police say a tractor-trailer jackknifed and hit a pickup truck that had slowed in the construction zone near Dingman Drive. The trailer then also hit a westbound straight truck.
Three people in the pickup, an adult and two children from Middlesex County were checked by EMS as a precaution, but were not injured.
The drivers in the trucks were also unhurt.
Traffic was jammed for about 90 minutes while the scene was cleaned up and the crash investigated.
