A 12-month-old girl has been killed after being attacked by her family's dog in northern New South Wales.

The baby died on the way to hospital after emergency services were called to a home in Inverell about 2.30pm on Saturday.

Upon their arrival, paramedics and police found the child had suffered critical injuries and began treating her at the scene.

The family’s Rottweiler dog was found in the backyard of the home by Gwydir Shire Council rangers. It has since been seized and impounded. It is not known whether the dog will be killed.