A woman and her pet dog are believed to have been thrown out of a ground floor window in Tate's Avenue, south Belfast.
Police have arrested a 31-year-old man in connection with an assault which neighbours said followed a domestic dispute shortly before 11pm on Monday.
Lesley Townsend from Tate's Avenue said: "I heard that when he started hurting the dog she opened the door and let the dog out, so he couldn't hurt it anymore. I just hope someone has taken it in and that it's safe.
She adds: "I didn't know anything had happened until yesterday morning (Tuesday). I seen a police car parked at the end of the alley way. I was out later walking my dog and two police ladies were at my door and were asking me if I heard anything because there has been a serious incident."
The woman injured in the incident is believed to be in hospital, her condition is not known, and neighbours are searching for a miniature schnauzer.