UPDATE: Two dead in fiery Melbourne freeway crash

Two people have been killed and one person has been taken to hospital with chest injuries following a crash on the Mornington Peninsula Freeway this afternoon.

The collision between multiple vehicles occurred just after 1pm near the Arthurs Seat Road exit at Dromana.

Investigators believe two cars were travelling south in single file and made contact before one crashed into a tree and caught fire.

The driver and passenger of the first car were both killed and are yet to be identified.

The driver of the second car was taken to hospital by helicopter with serious chest injuries.

Police said both drivers were travelling at "extraordinary speed" but it is not yet known if they knew each other.

The Mornington Peninsula Freeway will remain closed in both directions between Jetty Road and the Nepean Highway for the rest of the day.

Motorists have been advised to seek an alternate route.

Anyone with information has been urged to contact Crime Stoppers on 1800 333 000.