This is the moment four masked men used an ultra powerful hydraulic clamp to remove a safe from inside an armoured G4S security van.

Shocking footage shows the gang working against the clock to break the safe contained in the vehicle as its alarm rang out.

Police are now investigating the incident, which took place earlier this month at the Reevesland Industrial Estate in Newport, South Wales.

A source who sent the footage to MailOnline said that crew were using specialist equipment to blow the safe.

He said: 'It's called a hydraulic power pack. Some of the lads have been stealing from the fire service. They are perfect for prising open a safe in a security van.