The crash occurred at around 11:40am and resulted in the front carriage of the train de-railing and landing on its side. Two other carriages also derailed.
The train driver was trapped but has since been released by the CFA rescue crews.
CFA District 8 Operations Officer Paul Summons said there have been numerous injuries and people have been taken to hospital.
The driver of the semi trailer - which was carrying potatoes - is believed to have escaped injury.
“While we are scaling down our involvement at the scene, up to 200 metres of overhead high-voltage power lines remain down so the situation is still quite volatile,” he said.
“CFA crews will remain on scene for awhile yet to assist and our members have done a great job in difficult circumstances.”