A serious crash has left an 18-year-old driver dead with Mitchell Freeway northbound still closed as police investigate.

A white Nissan Patrol station sedan was travelling northbound on the Mitchell Freeway when the driver lost control of the car near the Powis Street exit, causing it to roll.

The teenage driver, who was the only person in the car, sustained critical injuries and was taken to Royal Perth Hospital, where he sadly died a short time later.

Police have blocked northbound lanes from Vincent Street to Hutton Street, with motorists being forced to exit the freeway as congestion builds.

Traffic is heavy back to Hay Street.

Drivers are being urged to avoid the area and find an alternate route.

Major crash officers are investigating the crash and are appealing for anyone who witnessed the incident to report to Crime Stoppers via www.crimestopperswa.com.au or by calling 1800 333 000.

Dash-cam or mobile phone vision relating to the crash can be uploaded directly to investigators via the following link, https://wapf.au.evidence.com/axon/community-request/public/glendalough