The OPP have confirmed that all lanes of the westbound 401 are blocked at Mavis Road in Mississauga.
They say that the closure is due to a structural issue with the overpass.
It’s not known how long the closure will be in effect.
ROAD CLOSURE: #Hwy401 WB at Mavis Rd – WB Highway CLOSED due to structural issues with overpass, traffic still able to get off at Mavis. ^cc
— OPP GTA Traffic (@OPP_GTATraffic) March 16, 2016