At least 20 people were taken to hospital, two in a critical condition, after two tornadoes cut a path of destruction across Victoria's north-east last night.
A severe storm moved across an area stretching from Cobram to Rutherglen just after 7.00pm (AEDT), ripping roofs from houses and uprooting trees.
Ambulance Victoria says a man in his 50s was flown to the Royal Melbourne Hospital with head, pelvic and abdominal injuries, while another man in his 50s was flown to the Alfred Hospital with serious head injuries.
Spokesman Paul Bentley says another man, who suffered spinal injuries when a tree fell on his vehicle, will be taken to Melbourne this morning.
"The sorts of injuries we've seen have ranged from serious head injuries, spinal injuries and fractures to cuts and bruising, so far paramedics have treated 20 people and taken them to hospital," he said.
"There's obviously the possibility with daylight that more people may come forward with injuries."
Tim Wiebusch from Victoria's State Emergency Service says several people were hit by flying debris.
"It's people that have been hit by flying objects, partial internal ceiling collapses of roofs, and we've had reports of trees coming down on cars and the like as well," he said.
"So certainly very extreme conditions in that area as a result of that tornado-like activity."
Buildings in Rutherglen's historic main street were severely damaged, with awnings ripped off and windows smashed.
The Murray Valley Highway at Bundalong was also closed for several hours after massive trees along a large stretch of the road were ripped to pieces.
'Buildings, homes demolished'
Police Sergeant David Arnold says the damage is quite severe.
"[It] demolished a number of buildings and damaged a number of homes and properties," he said.
"Windows, doors, also a number of chimneys have come down as well and they are big brick chimneys... and obviously a number of roofs have come off as well."
The SES says there were 150 calls for help, but they are expecting that number to increase as residents survey the damage this morning.
"The number of injuries that we've seen, and all looking like they were sort of trauma related with collapsing, or debris being picked up and thrown around, would indicate there's some pretty significant damage and I'd be surprised if there weren't a couple of properties flattened," spokesman Lachlan Quick said.
He said the number of injuries could have been worse if holiday homes in the area had been occupied.
"The worst of it has gone through Koonoomoo and Bundalong - and I know Rutherglen has been hit really hard," he said.
"I know there are quite a lot of holiday homes that are unoccupied and that may have assisted us with fewer injuries."
Meanwhile residents at Tamleugh North, about 112 kilometres south-east of Rutherglen, say they were also hit by another tornado.
A local resident, Mark, says the force of the winds was hard to believe, with fence posts ripped out of concrete bases and fully grown gum trees uprooted.
He says his parents were in one of the worst hit areas.
"Mum was inside holding the doors closed in one area and Dad was stuck in the shed," he said.
"He wasn't game to come out until it passed. He reckons it went for, I don't know, for about seven minutes or so."
© ABC 2013
12:38 EST Tropical Cyclone Jack has rapidly developed over the warm waters of the Indian Ocean in the past 24 hours, making it the 10th system to be named this season.