A dog has come to the rescue of its owner in America by calling the police.

John Stalnaker was having a severe seizure, so the specially trained animal bit into a device which alerted the police.

Operators tracked down the number and realised an assistance dog was calling for help.

Buddy, 18 months old, is able to press programmed buttons until a 911 operator is on the line.

Dispatcher Chris Trott can be heard on a recording of the incident saying: "Hello, this is 911. Hello... Can you hear me? Is there somebody there you can give the phone to?"

Arizona Police arrived three minutes later.

Scottsdale police sergeant Mark Clark said: "It's pretty incredible. Even the veteran dispatchers - they haven't heard of anything like this."

Stalnaker spent two days in a hospital and recovered from the seizure.

Clark said Buddy has made two other 911 calls when Stalnaker was having seizures. The seizures are the result of a head injury Stalnaker suffered about 10 years ago during a military training exercise.