An infant is fighting for life after being found in a locked car in Melbourne's south-west.

The one-year-old was unresponsive when emergency crews arrived around 3.15pm.

Watch the video above

The boy was reportedly left in the parked car at the Brook Hotel on Sneydes Road, Point Cook.

The temperature was close to 40 degrees.

The boy was reportedly left in the parked car at the Brook Hotel in Point Cook. Credit: Google Maps

"Ambulance crews treated and transported the boy to hospital in a critical condition," Victoria Police told 7NEWS.com.au.

A crime scene has been established as police investigate the circumstances surrounding the incident.

More Victorian news on 7NEWS.com.au

It's thought the boy could have been in the car for up to five hours.

He is now at the Royal Children's Hospital in a critical condition.