A 60-year-old man has been burned fighting a grassfire that is believed to have turned into the large, fast moving out-of-control bushfire which has burnt out 750 hectares in Victoria's northeast.
Ambulance Victoria spokesman John Mullin said the man suffered burns to about 18 per cent of his legs, but after being treated by paramedics refused to go to hospital on Sunday afternoon.
Winds picked up the fire, which has now burned out 750 hectares, and is heading towards Boho and the Hume Highway.
More than 40 CFA tankers are battling the blaze but the five aircraft that were assisting have been grounded because of nightfall.
The CFA says there is an imminent threat to lives and property and it may be too late for people in the Boho area to leave.
The Emergency Alert affects the area bounded by Harrys Creek Road, Hayes Road, Boho Church Road and School Road.
The CFA will carry out an investigation into how the fire started but at the moment its focus is on getting it under control.