Police are responding to an incident at Bourke Street Mall, Melbourne, with reports of a car going up in flames.
Suki Singh told SBS News he saw a "massive fire" with "police everywhere" near the corner of Bourke and Swantson streets.
"There were choppers flying above ... People were running," he said.
Another person at the scene said: "I saw people running, screaming. It was really terrifying".
"I've never seen a fire that big before."
SBS News has contacted Victoria Police for comment.
Premier Daniel Andrews tweeted that "details are still unclear".