A police helicopter was diverted from the hunt for Malcolm Naden to help chase down two alleged criminals who took police on a 170 kilometre, two-hour pursuit through the Hunter yesterday.

The chase, which included about 75 kilometres the wrong way along the F3 and an alleged carjacking, eventually ended on a remote Coalfields road after police used spikes then rammed the stolen BMW and arrested a couple.

Highway patrol officers manned freeway on-ramps to stop vehicles entering the southbound lanes after an allegedly stolen Ford Falcon XR6 sped north from near the twin service stations at Warnervale to the northern end of the F3 at Beresfield.

Police allege a couple in a BMW 120i was then robbed of their vehicle at gunpoint after the XR6 was driven off the road near a Beresfield service station. A man with a pistol is alleged to have threatened them before taking their grey sedan.

Police followed the BMW along the New England Highway and through streets in Maitland, including its main High Street, before heading towards the Coalfields.

A police helicopter, Polair 2, then joined the chase, with crew able to keep an eye on the wanted car as other officers continued at a safe distance behind. It is alleged the BMW was driven at speeds in excess of 200km/h at times.