A shopkeeper was terrified when a massive water monitor lizard ran across the floor.

Aum was doing her makeup at her desk when the reptile skittered into the front room of the property where she sells groceries in Chonburi, eastern Thailand.

CCTV footage shows the beast scuttling past Aum as a pet cat chased after it deeper into the house on August 7.

The stunned woman stood on her sofa, waiting for the creature to leave through another exit.

She said: 'I was shocked when it entered the house. But then I saw it wasn't as big as some of the others, so I wasn't that scared. It eventually left on its own.'

Asian water monitor lizards normally live in canals, swamps, sewers and ponds in cities in Thailand. They feed on fish, snakes, frogs and scraps of food left by humans.

The reptiles are aggressive when threatened and have a mildly venomous bite which sometimes carries harmful bacteria. The Godzilla-like reptiles are also a protected species in the country so their population thrives.