Girl, 4, mauled in Melbourne a day after woman received critical injuries in separate dog attack

A four-year-old girl has been rushed to hospital after being mauled by a dog in Melbourne, a day after a woman received critical injuries in a separate attack.

It is understood the girl was bitten by a dog that was on a lead at the time.

The incident, which happened at a recreational reserve on Churchill Ave in Baybrook at 1.55pm on Friday, has been referred to the Maribyrnong City Council.

The girl suffered non-life-threatening injuries.

Police say the owner remained on the scene and was assisting with inquiries as officers try to determine the exact circumstances surrounding the incident.

It comes after a woman in her 50s received critical injuries in a dog attack early on Thursday morning.

The 54-year-old was believed to be on a morning run in Winchelsea when she was attacked, 7NEWS reports.

Police had to use capsicum spray to fend off two dogs circling the injured woman.

The woman is in hospital fighting for her life, with injuries to her upper and lower body.

The dogs have been taken by council rangers.

Anyone who witnessed either incident or has information that could assist police is urged to contact Crime Stoppers on 1800 333 000 or submit a confidential report online at www.crimestoppersvic.com.au