Man with knife threatens commuters at Perth station

Police are searching for a knifeman who threatened multiple people at a Perth train station this morning.

A witness told 9News brave bystanders who noticed the knife helped others run to safety at Leederville, close to the centre of Perth.

Luke Fox was at the station at 7.30am.

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"We were all heading up the stairs at Leederville and someone yelled, 'There's a man with knife', and we all, everyone started walking back," he told 9News.

"A lady got us all to go back downstairs and you could see a man at the top yelling at people, I couldn't really see what he had."

The moment lasted just seconds but was enough to terrify those there.

Eli Morrison was also at the station.

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"There was a guy at the top yelling so everyone kind of stopped and bolted back down the steps," she said.

"They were saying he had a knife."

No one was injured.

The knifeman made a run for it, and police issued an alert, urging anyone who saw him not to approach him.

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The police canine squad and fixed wing plane both searched for him.

He was last seen wearing a black tracksuit top, black tracksuit bottoms with white writing on the leg, white runners and carrying an insulated shopping bag.

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