A two-year-old girl has died after her family’s car was caught up in a four-vehicle crash allegedly caused by a speeding driver in Melbourne’s inner west.

The toddler was travelling in a Mazda with two adults and her two brothers along Dynon Road in West Melbourne when the collision occurred shortly before 4.30pm on Wednesday.

Police allege a silver SUV struck the Mazda as they both exited the newly opened West Gate Tunnel, sending it into two other vehicles in a devastating chain-reaction crash.

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The young girl died at the scene.

The male driver and female passenger, both aged 30, and her brothers, aged 11 months and four years, were rushed to hospital. 

The driver of the Mazda remains in a critical condition.

Footage from the scene shows the family’s car crushed and extensively damaged, with debris strewn across the roadway. 

The silver SUV also sustained significant front-end damage.

The SUV driver was taken to hospital with serious but non-life-threatening injuries.

Police arrested him at his bedside on Thursday and he remains in hospital under police guard.

The drivers of the two other vehicles involved — a 30-year-old woman and a 40-year-old man — were assessed by paramedics but did not require hospital treatment.

Investigators are appealing for the driver of a dark-coloured Tesla seen near the crash site to come forward, believing the vehicle may have captured the collision on dashcam footage.

“There is no suggestion this vehicle was involved in any offending and is simply a potential witness to the collision,” police said. 

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