Here is our exclusive footage from the incident. Simply click on the green button to view.

More than 15 cop cars sped after the black Mercedes as it smashed through train barriers on Horsham Road at 11am this morning.

It's thought the three men inside the motor were being hunted after holding up a G4S Cash Services van at the BP Garage on the A23.

Witnesses described how wreckage from the barrier sparked a blaze on the railway embankment after it jammed under the wheels of a train - which had missed the car by seconds.

A mum and her young son described how the speeding motor had missed them by a matter of inches.

She said: "We were both screaming, I thought we were both going to die."

Another witness added: "I was just on the corner walking my dog, going home when a black Mercedes shot past at high speed and I thought 'they're either going to turn right or go straight through the barrier'.

"They were so, so lucky they weren't hit. Fifteen or so police cars were in high pursuit of it and they followed it through the hole. There were mums with little children who were holding onto the barrier."

The suspected getaway vehicle continued on to Albany Road where it crashed.

Residents explained how the force of the impact had popped open the boot leaving cash fluttering down the road.

A workman at Albany Road said: "I just heard a crash bang and I came out of the house that we were working on.

"There was money all over the road and then lots of armed policemen ran down the road with guns."

The armed raiders are then thought to have stolen another vehicle on Chiltern Close after punching the car's owner.

Resident Sue Lewis, 49, said: "We heard the sirens first and I said, 'there must have been an accident'. Then my neighbour told me that men had come running down the road and punched an old man and taken his car.

"The ambulance took him to hospital. My neighbour said that she thought he'd been shot because he was clutching his shoulder but I think they just punched him."

The Observer understands that the men then abandoned the second vehicle and boarded a Southdowns PSV bus by the Ifield roundabout.

Armed cops and dog units all boarded the packed bus and three men were led away in handcuffs while a police chopper circled overhead.

A police spokesman confirmed that the men were being tracked in connection with a robbery.

He said: "Three men, armed with a firearm, held up an ATM cash delivery vehicle, at about 11am and fled with money.

"In a joint Sussex Police and Met police operation, armed officers were quickly at the scene and three men were arrested nearby. No shots were fired. A weapon was recovered along with the stolen cash.

"Three men have been arrested and are helping police with their enquiries.

"Any witnesses are urged to contact police on 0845 60 70 999 or Crimestoppers on 0800 555 111."

Did you see anything? Call the Observer on (01293) 845055 or email matthew.gaw@sussexnewspapers.co.uk

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