Three people have been transported to hospital when it is believed two cars collided head-on in Majura early this morning.

Just before 5am ACT Emergency Services responded to a motor vehicle crash on the Monaro Highway at the Malcolm Fraser Bridge.

An ACT Emergency Services spokesperson said: 'The two-car high-speed collision caused significant injuries to three patients, all three have been transported to hospital in a stable conditions.'

The Northbound lanes of the highway were closed heading towards Pialligo for some time following the crash.

Police urge anyone who witnessed the collision, or who has any footage of it, to contact Crime Stoppers on 1800 333 000, or via the Crime Stoppers ACT website.