Bystanders applied first aid before paramedics attempted to resuscitate him at the scene, but he could not be saved.
On Sunday, people left flowers and cards at the station. One woman told the ABC that Becker “couldn’t hurt a soul”.
“All he wanted to do was help people,” she said.
“He would do anything to help anyone; he’d give the shirt off his back to a random person.”
She said Becker’s family were still coming to grips with the circumstances of his death.
Becker worked as a security guard at the Alfred Hospital, which released a statement on Sunday describing him as a “quiet hero”.
“We are deeply saddened by the passing of young security officer, Aidan Becker,” the statement read.
“Aidan’s colleagues at The Alfred describe him as a dedicated, respected, and much-loved member of our security team.
“He will be remembered for being full of life, and for his positive energy, kindness and dedication.
“He was a quiet hero who gave his all for those around him.”
Yarrambat Football Club, where Becker was a former player, paid tribute to him, saying their hearts were “incredibly heavy”.
“Aidan was the kind of teammate every club hopes for – selfless, team-first and always willing to put others before himself,” the club said in a statement.
“His impact reached far beyond the game and the sadness of his loss is being felt deeply across the entire community.”
In response to the attack, Premier Jacinta Allan announced the deployment of the Government’s new violence reduction unit to Mernda.
The unit will work with police and Department of Education staff with the aim of addressing youth crime at its roots.
“We created the violence reduction unit for this reason, to work with the community in the aftermath of violence and prevent further trauma,” Allan said.
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