Northbound traffic queued at least 12km on Sydney's M7 at Horsley Park after six-vehicle accident

Motorists travelling northbound on the M7 Motorway are facing lengthy delays following a six-vehicle accident near Horsley Drive in Horsley Park.

Emergency services and incident response crews are on site.

Southbound lanes have not been impacted.

Northbound traffic is queued back at least 12km, but all northbound lanes have now been reopened and traffic is expected to recover.

The Transport Management Centre has advised motorists to consider using Wallgrove Road as an alternative and then rejoin the M7.