A grandmother's tree pruning went wrong when a huge branch fell on her outside her home.

CCTV footage shows the pensioner, Nai, 89, trying to cut off a portion of the massive hardwood tree that canopied their home using a saw she tied to a long stick.

She could not remove the bough standing from a ladder, so she climbed down and tugged on it instead before it collapsed right on top of her.

Fortunately, the old woman was not seriously hurt and went on to cut the large branches into firewood with her husband, Pai, 91, in Saraburi, Thailand, on September 16.

Their grandson Sommai Piroonyoi said: 'My grandparents wanted to remove some parts of the tree that were blocking the sunlight, so they took a saw and cut the branch.

'My grandma pulled the branch to remove it on her own and crashed onto her. We have access to the CCTV to check on them occasionally, and we almost had a heart attack when we saw it.'

Sommai added a small branch hit her on the back but was not injured.

He added: 'She still stood up and helped my grandpa clean away the branches. She is amazing and so tough'