An explosion has caused extensive damage to a Waroona bank this morning.
The police Bomb Response Unit and Arson Squad officers are investigating the blast at Bendigo Bank on South Western Highway about 3.40am.
An ATM at the front of the bank has been blown apart by the blast and parts of the machine are strewn on the pavement.
Detective Senior Sergeant John Mundy said three people were believed to have been involved in the blast and one of them might have been hurt in the explosion.
A dark coloured Holden Commodore ute, which was stolen from a home in Golden Bay two days ago, was captured on CCTV at the scene.
The car was discovered burnt out on the corner of Wanjeep Street and Silvergum Avenuein Coodanup about 7.30am.
Officers on South Western Highway have recovered notes of cash believed to have been from the bank.
Police have asked residents who found cash in the area to return it and contact Crime Stoppers.
Det. Snr Sgt Mundy said police believed the offenders were targeting the ATM and had taken an amount of cash but the amount would not be known until bank staff determined how much was missing.
He said the culprits could have seriously hurt themselves or others with the blast, which was just metres from homes and a local school.
"You can see from the damage to the bank that this was a very violent explosion and people risk injuring themselves and killing themselves and innocent members of the public," he said.
Police have asked anyone who witnessed the stolen car or noticed people acting suspiciously or showing injuries consistent with those caused by broken glass or fire to contact Crime Stoppers on 1800 333 000.
The cordoned off area of South Western Highway is expected to remain closed until this afternoon.
At least four fire trucks were at the scene this morning and police set up a 200m exclusion zone around the area.
Pauline Schmidt raised the alarm after noticing damage to the bank on her way to work at 3.45am.
Ms Schmidt said she became suspicious when she was tailgated by a white Ford F250 with it's lights on full beam during her drive on South Western Highway.
"I saw the car pull into the bank and when I drove past I thought 'oh my god the bank's been blown up' so I called the police," she said.
"I thought I was imagining things because there was nothing left of the shop, there was glass shattered everywhere."
Night shift worker Yvonne Wheeler heard the explosion from her workplace 500m away.
"We thought a gas container had gone off. It was a pretty loud bang, we could hear it inside the building," she said.
"It scared me so much I lifted my feet on to the chair."
Ms Wheeler said she heard a car speed off from the bank shortly after the explosion.
Locals are baffled by the blast in the usually quiet town.
"Nothing like this ever happen. Nobody ever comes here, except to pass through," one local said.