Baby girl in a coma after car ploughs into bedroom of Victorian house

A four-month-old girl is in a coma after a car crashed into the bedroom of a Geelong house overnight.

CCTV captured the moment a car speeding along Fellmonger Road mounted a roundabout and became airborne just after 8.30pm.

The car crashed through the property’s fence and into the house in Breakwater, near Geelong.

Four-month-old Isobelle suffered critical head injuries and was taken to the Royal Children's Hospital by helicopter, where she remains in a coma.

Her parents Natalie and Dylan, who were in the bedroom at the time, suffered only minor injuries during the incident.

Neighbours said an occupant of the house lashed out at the drive and struck him with a fence paling, after the crash.

"This guy was hitting this other fella and knocked him to the ground," neighbour Norma Ilic said.

A 20-year-old Grovedale man is under police guard in Geelong Hospital.

Detectives from the Major Collision Investigation Unit were at the scene earlier today.

"The intersection is well lit... nothing that we can see here with road conditions and weather conditions would have contributed to the accident," Detective Sergeant Andrew Kilpatrick said.