A girl in a wheelchair was bitten by a dog which was set on her by two men, police have said.
The 12-year-old was out with her father when she was attacked in Lings Wood, Northampton, on 3 October.
She became upset about the men and the "pit bull-type" dog passing too close, so one of them commanded it to "get her".
Police said the girl's arm guards, which she wears due to her disability, prevented her from being injured.
Insp Kev Byrne from Northamptonshire Police described it as "an absolutely disgraceful incident".
"It is not a case of a dog being out of control, but being used as a weapon in an assault on a very vulnerable girl," he said.
'Appalled by incident'
"Had it not been for the victim's arm guards, she could have been seriously injured," Insp Byrne said.
"I know local residents will be appalled by this incident and I would urge anybody with any information to contact us immediately."
The two men are described as black and in their 30s.
One was about 6ft (1.8m), clean-shaven with short black hair and wore a blue T-shirt and jeans. The other was 5ft 10in (1.78m) and had "medium length Afro-style hair", police said.
The dog is described as a black and white pit bull-type breed.