The M80 Ring Road is closed in both directions near Sydney Road due to a police incident.
There are significant delays building in both directions, according to the Department of Transport.
Greensborough-bound traffic is queuing from the Tullamarine Freeway, while Altona-bound traffic is congested from Edgars Road.
The department suggests drivers exit the freeway early then use Camp Road, Mahoneys Road and Edgars Road to avoid the closure.
Motorists travelling between the Hume Freeway and the M80 Ring Road should use Sydney Road and Cooper Street instead.
“We ask motorists to be patient and to follow the direction of overhead signals and emergency services,” the department said.
“This closure is under Victoria Police control. The M80 will re-open when it’s safe to do so.
“Our signals team is monitoring conditions and will adjust traffic lights as needed to minimise congestion for detouring traffic.”
Real-time traffic conditions are available at traffic.vicroads.vic.gov.au or via the VicTraffic mobile app. The latest public transport information and network status is available at ptv.vic.gov.au or in the PTV mobile app.