This is the shocking moment a pit bull launches an unprovoked attack on a woman in front of her grandchildren.

Video shows Brenda Rigdon of Florida sat in a garden chair nervously gearing up for the ALS charity ice bucket challenge.

But as soon as the soaking takes place, a large canine jumps up and bites her hard on the face.

WARNING: GRAPHIC CONTENT

The senior is heard squealing in pain as the animal drags her down to the ground.

She rolls on her front with her face in the grass.

Mrs Rigdon's husband, Charles, who was busy filming the event, drops the camera to help.

As the view cuts to the sky, commotion can be heard in the background.

'Grandma are you OK?' one of Mrs Rigdon's grandchildren asks.

'No, go get me towel please.' she weakly responds.

The child says he can see blood on Mrs Rigdon's arms and all over the dog.

Caught on camera: This is the shocking moment a pit bull launches an unprovoked attack on a woman in front of her grandchildren

Terrifying: Video shows Brenda Rigdon of Florida squealing in pain as the animal drags her down to the ground - she rolls on her front with her face in the grass

Lasting damage: At the end of the video, photo stills show Mrs Rigdon with stitches running from her lip up her left cheek

At the end of the video, still images show Mrs Rigdon with stitches running from her lip up her left cheek.

Although the incident took place last summer, Mrs Rigdon said she wanted the clip releasing online only when she was ready.

Her son posted it to YouTube on February 27 with many viewers offering their condolences.

Apparently the pit bull, named Kilo, was put down shortly after the attack once he'd been checked for rabies.

Mrs Rigdon's son said the pet wasn't properly trained and was kept principally for breeding purposes.

He concluded: 'This should serve as a warning to all pet owners. Unless you are going to take the time to make an animal a pet then it will remain an animal.'