This is the shocking moment a homeless tourist was caught stealing food from a parked delivery rider's motorcycle.

Biw Chutikarn, a Grab rider and the owner of the vehicle, was with his girlfriend when they allegedly encountered the foreigner rummaging through his cargo box in Bangkok, Thailand, on October 15.

Footage shows the couple confronting the scruffy tourist sitting on the scooter, holding the container bag.

The woman can be heard telling the man to get away from the vehicle and go away, however, he can be heard trying to reason with the locals.

The barefoot individual stood up and grabbed a plastic bag.

Biw Chutikarn said: 'The foreigner approached us, claiming my boyfriend was his friend. We avoided him, but he returned later.

'We found him raiding our parcel bag on the motorcycle and stealing the mobile phone's charger in front of the vehicle. 

'I was able to manage to take it back from him. I don't know where he is from.'

Biw reported the encounter to the police, however, she said that the authorities could not do anything about it.

She said: 'We can't do anything with crazy people.'