Mother, son killed in horror crash north of Melbourne
One woman and one boy died in the crash at Molesworth. (9NEWS) 9NEWS
A mother and her son have been killed in a single-vehicle crash on the Goulburn Valley Highway at Molesworth, north of Melbourne.
The 34-year-old woman and the eight-year-old boy were both killed on impact when their four-wheel-drive rolled just after 2pm today.
Two young girls also involved in the crash suffered critical injuries and have taken by helicopter to the Royal Children's Hospital in Melbourne.
A two-year-old girl is in a serious condition with an injury caused by her seatbelt, while the six-year-old girl has fractured her pelvis and suffered abdominal injuries.
Both girls will undergo surgery for their injuries tonight.
Police are yet to determine if speed or fatigue were a factor in the crash, and will prepare a report for the Coroner.
Anyone with information about the crash is urged to contact Crime Stoppers on 1800 333 000.
The two deaths brings Victoria's road toll for this year to 58, up from 53 at the same time last year.
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