Police have arrested a 37-year-old man from Parafield Gardens following a police pursuit in the northern suburbs yesterday afternoon of a stolen car allegedly involved in a robbery at the Pooraka post office.

Police were alert to the fact that at about 3.23pm, a man allegedly armed with a firearm threatened staff at the post office and fled in a white Telstar sedan stolen from Northfield earlier in the afternoon.

The suspect vehicle was spotted by police patrols at about 3.50pm and pursued until the helicopter was in position to take over and manage the pursuit safely from above.

Spikes were deployed and the suspect vehicle did run over the spikes which eventually assisted police with a safe outcome when the vehicle came to a stop at the corner of Waterloo Corner Road and Salisbury Highway at about 4.20pm.

The driver was arrested and has been charged with aggravated robbery, drive to evade police, acts to endanger life and numerous traffic offences.

It is expected that the man will appear in Court later today.