Police have said they have no record of an attempted child snatching attempt after a woman claimed she prevented an abduction in Mitcham by chasing a man through the streets.

Natalie Murphy posted on her Facebook page that she saw a man grab a five-year-old girl from a bus in Mitcham Eastfields while it paused at traffic lights.

In the post, which has been shared almost 650 times on Facebook, Ms Murphy claims that she ran after the man for over 10 minutes in knee-high four-inch boots, before jumping on his back and knocking him to the floor.

She ended the post: “I don't understand how I was the only person to do anything????? What if this little girl was someone they loved?"

Hundreds of people have shared this status since it was posted on Monday

“Shouldn't we all be working together to stop these monsters not sitting back and waiting for other people to stand up and take charge????????”

Although Ms Murphy said she was given a crime number after the chase, which she said took place on Monday, April 11, police have denied any knowledge of the event.

She spoke to the Wimbledon Guardian briefly yesterday but has not returned calls since.

The post has been shared widely across social media, leading several people to directly ask the police via Twitter if the attempted abduction really happened.

A spokesman for Merton police said: “I have been looking into this further and I have been unable to find any instances that match this description.”