Eric Edgar Cooke terrorised the city of Perth for years before he was caught and executed

Serial killer Eric Edgar Cooke became the last person to be executed in Western Australia when he was hanged in Fremantle Prison on October 26, 1964.

Over five years, Cooke murdered at least eight people in opportunistic attacks, with no obvious common traits between the victims.

For years, it was not believed the murders were linked, and innocent men were wrongfully convicted of two of the deaths.

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But police had a breakthrough in the case thanks to a lucky break.

In August 1963, a rifle was found in a bush on a residential street in Mount Pleasant.

The rifle was matched to two of the deaths by a ballistics test.

Police then placed a dummy rifle in the bush tied to a fishing line.

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When Cooke returned to get the rifle, he was arrested.

After being arrested, Cooke claimed responsibility for eight murders and 14 attempted murders.

He also claimed to have killed Jillian Macpherson Brewer and Rosemary Anderson, for whom two innocent men were already in jail.

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Before being walked to the gallows on October 26, 1963, Eric Edgar Cooke took a Bible from the chaplain and swore he killed Brewer and Anderson.

Darryl Beamish served 15 years for the murder of Brewer and John Button served five years for the manslaughter of Anderson.

It was decades before those convictions were quashed.

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