Officers from Prahran police station were called to Trawalla Avenue about 8.25pm on Saturday.

Witnesses reported seeing a Subaru Outback crash into a parked car, before hitting an oncoming car and then reversing into another parked car.

Police arrived on scene and breath-tested the driver, a 30-year-old woman from Toorak.

Senior Constable Adam West said she was required to attend a station, where she provided a blood-alcohol reading of 0.336 per cent.

The woman's car was impounded and she is expected to be charged on summons with drink driving and numerous other traffic offences.

A few hours later, police intercepted a speeding ute on the Tullamarine Freeway in Strathmore.

Officers pulled over the Toyota ute about 1am to find six men all aged in their late teens were in the four-seater vehicle.

In addition to exceeding his passenger restrictions, the P-plater driver also tested positive for drugs.

The Sunbury man had his car impounded and is expected to be charged on summons for drug driving, speeding, exceeding passenger restriction, failing to obey licence condition and failing to display P plates.

The four passengers in the rear of the ute also each received a $303 infringement for not wearing seat belts.

Fawkner Highway Patrol Sergeant Michael Free said the circumstances were a disaster waiting to happen.

"With all of these conditions, this situation could end in tragedy," he said.