A 28-year-old woman has been bailed to appear before Ararat Magistrates Court on March 27, after an alleged assault in the town on Sunday night.

The woman was one of four arrested after the alleged incident on Mitchell Road at 6pm.

In a statement, Victoria Police said investigators believed the 66-year-old was assaulted "after being involved in a verbal dispute with four other people".

"The woman received life-threatening head injuries and has been flown to a Melbourne hospital for treatment," the statement read.

On Tuesday morning, Ararat Detective Acting Sergeant Jason Boyd said the 28-year-old had been charged with one count of assault. He said a 55-year-old man, a 51-year-old woman and a 32-year-old man had all been released pending further inquiries.

Update 11.17am Monday:

Statement from Victoria Police:

"Investigators believe a 66-year-old woman was assaulted in Mitchell Road about 6pm Sunday after being involved in a verbal dispute with four other people.

"The woman received life threatening head injuries and has been flown to hospital for treatment. Police attended and arrested two men and two women who are currently assisting them with their inquires."

Ararat Senior Constable Calvin Laugesen said the woman had been flown to the Alfred Hospital in Melbourne, and that the investigation was ongoing.

11am: Ararat police have confirmed a crime scene has been established at Mitchell Road.

The entry to the road from the Pyrenees Highway has been closed off with police tape, while officers remain on the scene.

The Mail-Times has sought further information about the operation from Victoria police.

More to come.

While you're with us, you can now receive updates straight to your inbox twice weekly from the Wimmera Mail-Times. To make sure you're up-to-date with all the news from across the Wimmera, sign up below.