A 12-year-old girl was being treated for "life-changing" injuries today after being mauled by a rottweiler in a park.
The dog's owner was arrested after the youngster was set upon in Morden Park, south London, on Saturday, as she picked flowers.
She underwent emergency surgery and is expected to need more operations in future, sources confirmed.
The animal, which bit her on the head, has been seized by police.
A Scotland Yard spokeswoman said the dog was not a banned breed.
She said: "We were called at 15.06 to a park in Hillcross Avenue to reports of a dog attack.
"The ambulance and police attended to find a 12-year-old with dog bite injuries to the head.
"The child was taken to hospital where her injuries were described as life-changing.
"A 57-year-old man attended a south London police station and was arrested under section two of the Dangerous Dogs Act. He was bailed to return on a date in May.
"The dog has been seized by police."
It is the latest in a spate of dog attacks on children.
Earlier this month, 18-month-old Zumer Ahmed was mauled to death by her uncle's dog.
She was attacked by the animal, believed to be an American bulldog, at her home in Cotton Walk, Broadfield, Crawley, West Sussex.
Last month a two-year-old girl had facial reconstructive surgery after she was mauled by her family's French bullmastiff in Eltham.Reuse content