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Warning: This story contains details and content that some readers may find distressing.
A man has allegedly threatened to kill innocent tram passengers at knifepoint after going on a stealing spree in Melbourne, according to police.
The man, 57, allegedly robbed a 7-Eleven on Collins Street before boarding the route 48 tram at the corner of Collins and King streets at 8.25am.
Police arrived at the tram before it reached the next stop.
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9News understands the driver locked the man inside the tram to assist police officers, who were getting into position outside.
The man allegedly started threatening passengers when he was unable to leave, grabbing one woman by the head and holding her at knifepoint before shouting that he would kill her along with others on the tram.
In video footage taken by a passenger, he can also be heard telling the driver to "open the door" before telling police to shoot him if they "wanted them [the passengers] to live".
Police Tasered and arrested the man once the doors were opened.
No one else was hurt.
The incident has prompted calls from the Transport Union for increased police presence on and around Melbourne tram lines.
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