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A police investigation is under way after a gunman went on a rampage, threatening people and plunging a small town in Western Australia's Wheatbelt into lockdown.
The terror began about 100 kilometres south of Perth when a black Mitsubishi Triton stopped at the scene of a car crash on Albany Highway in Bannister at 5.20pm on Saturday, police said.
The five motorists from that car wanted to help the occupants of a red Holden Commodore sedan that had crashed.
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A passenger from the Triton ute went over to the crashed car when a man carrying a firearm and a woman appeared from nearby bushes, police said.
The good Samaritans were allegedly shot at twice before fleeing.
Next, a couple from Williams tried to help at the crash site.
They were also confronted by the same pair and their gold Volvo station wagon was stolen at gunpoint, police said.
The alleged offenders drove nearly 300 kilometres to the small town of Merredin.
It was there about 10.30pm that it's believed the gunman and woman followed another motorist.
The man pointed a firearm at the female driver, who managed to get away, police said.
The ordeal plunged the town into lockdown, with locals told by text message to protect themselves and stay indoors.
A total of 90 people barricaded themselves inside the local pub.
"We'd just called last drinks at 10 to 12 and then the phone rang and it was the police saying to make sure no one left," pub owner Jason Williams said.
Just before midnight, the 24-year-old woman who was with the gunman was arrested.
The gunman continued driving, stopping a kilometre from the town before turning the gun on himself.
Police tried to revive him but he was declared dead.
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Police and community leaders said what happened "doesn't get any scarier".
"It's a tragic event and it affects many people," Merredin Shire president Mark Mckenzie said.
"To have a firearm pointed at you like what happened in this situation, no doubt would have been terrifying for those people involved," WA Police Commander Scott Warner said.
"The strength of the West Australian community is that as community members, we like to help each other out, and I'd hate to see a time that that changes."
Police are looking for dashcam footage.
Crisis support is available from Lifeline on 13 11 14.
Support is available from Beyond Blue on 1300 22 4636.
