Sydney Armed Robbery Attempt Filmed On Phone

The attempted armed robbery of a cash van in Australia has been caught on camera using a mobile phone.

Someone is heard shouting "Call the police, call the police" during the short clip as three armed men surrounded two guards outside the armoured vehicle in Sydney.

"Don't let them see that you've got your phone. He's carrying an AK-47, an assault rifle," another voice is heard saying in the background.

Moments later, armed police arrived at the scene outside a shopping centre and sealed off the area.

Witnesses said the gang - wearing balaclavas and armed with a pistol - pulled up in front of the Armaguard truck in a large black vehicle.

One of the guards was struck on the back of the head, possibly with the butt of a firearm.

And while one warning shot was fired into the air, no money was handed over.

Leichhardt Police Commander Michael O'Toole said the attempted robbery appeared to have been planned.

"Given the fact they were wearing balaclavas and armed, it would appear there was some degree of planning that's gone into this," he said.

"Of course we are worried they will strike again. It's a concern for something like this to happen at that time of the day when there are so many people around."

Witnesses described the attack as "crazy".

"They had tried to open the passenger side door first and when they failed they went around the back of the truck to open it manually," witness Barry Zambrano told Australia's Channel Nine news.