Five out of the seven people killed in a fiery crash on a Florida highway were children that were reportedly heading to Disney World, authorities said Friday.

Florida Highway Patrol Lieutenant Patrick Riordan said the other two killed in the crash were men driving semi-trucks.

The crash involved multiple vehicles and took place Thursday afternoon on Interstate 75 near Gainesville, Florida.

Mr Riordan said preliminary information suggests that a car and a tractor trailer both heading northbound on I-75 collided with one another and went through a guardrail, and entered the southbound lanes. Soon, those two vehicles struck a large passenger van and another semi-truck. A fifth vehicle then also hit some of the passengers and debris on the roadway.

The Alachua County Fire Rescue posted a photo showing a tractor-trailer in flames with another vehicle under it in the left side.

Eight other were hurt. Some passengers were hospitalised for critical injuries.