LONDON, ONT -- It was a busy day for provincial police in southwestern Ontario, as there were multiple collisions involving tractor trailers on the 401-series highways.

As of 6:30 a.m. there had been four reported collisions involving tractor trailers since 1 a.m.

The first report came in just before 1:30 a.m. on Highway 401 westbound near Colonel Talbot Road. That collision has since been cleared and no injuries were reported.

The second collision saw a tractor trailer crash into the ditch along Highway 402 near Nauvoo Road just before 4 a.m.

Around the same time a tractor trailer crashed into a ditch along Highway 401 westbound near Union Road in Elgin County.

The fourth incident occurred in Essex around 5:20 a.m. when a tractor trailer became jackknifed in the westbound lanes near Puce Road. That collision has been cleared.

Meanwhile the eastbound off ramp to Highway 2 from Highway 401 was closed to remove a vehicle from the ditch there.

There were also closures along Highway 401 in Chatham-Kent through the afternoon.

As of 9:30 a.m. West Region OPP were reporting 194 collisions since 6 p.m. Wednesday, while a typical night involves roughly 20 crashes.

Road conditions have forced bus cancellations throughout the areas surrounding London, and a blowing snow advisory was in place Thursday morning.