Multi-car crash causing M1 traffic delays

8.35am: All southbound lanes of the M1 Princes Motorway have reopened after an earlier multi-vehicle crash but traffic remains heavy.

8.25am: Traffic is heavy southbound on Mount Ousley after a multi-vehicle accident on the M1 Princes Motorway. 

One southbound lane is closed as a result of the crash, which happened near the New Mount Pleasant Road overpass just after 8am on Thursday.

Traffic in the area is heavy and motorists have been told to expect significant delays.