A car, a truck, and a 4WD towing a horse float have all crashed on a major freeway.

The vehicles collided on the Westgate Fwy at Southbank, in Melbourne’s inner city, about 12.10pm on Saturday.

The drivers of the cars were both seriously injured in the crash, and were taken to hospital.

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“The truck driver was not injured, and no animals were injured,” Victoria Police said.

The exact cause of the crash is at this stage unknown, but investigations are ongoing.

Thoroughbred horse Salsa Fellow was in the float when the cars crashed and was pulled from its race at Caulfield.

The horse reportedly sustained bruises and swelling from the crash.

Traffic on inbound lanes between Montague St and the Burnley Tunnel were impacted as lanes were closed and diversions put in place, but the roads have now been cleared, according to VicTraffic.

Anyone who witnessed the crash or who has relevant information or dashcam footage is urged to contact Crime Stoppers.