A Thai street seller cheated death after a Buddhist monk stabbed him in the neck to prove that the lucky amulets he was hawking had no supernatural powers.

The hawker was selling 'occult' charms when he began arguing with the monk over their abilities last Friday afternoon in the popular China Town area of Bangkok, Thailand.

Victim Nai Atchawanit, 30, is said to have told monk Niwan Phrachakasem, 54, that the lucky amulet around his neck was blessed by higher powers and could repel attacks.

Niwan allegedly said he would disprove it and produced a 12-inch long knife from under his orange robes before slashing at Atchawanit's head and neck.

Video footage shows the English-speaking tourist holding the victim up (left) to try and prevent blood loss before he slumps to the ground (right)

Harrowing video footage shows the injured man falling to the ground in a pool of blood, before a brave tourist intervened and held him up to prevent blood loss.

With the monk a few yards away holding a knife, the tourist was heard calling for help while many locals hurried by - too afraid to intervene.

The English-speaking man, in white t-shirt and orange shorts, has been credited with helping to save the victim's life.

Niwan Phrachakasem, 54, (left) stands around while the English-speaking man tries to save his victim and he is detained by the police (right)

Police arrived on the scene and arrested the knifeman monk who told police that the victim had 'encouraged him to stab him to test the power of his amulet.'

Officers detained Phrachakasem in custody while they investigate his credentials as a monk and wait to interview the victim, who was last night in a critical condition at a nearby hospital.

Lieutenant General Satit Mitrak from the Phlap Phla Chai Road Police Station said: 'He (the street seller) came to talk to the public about the power of the occult, spirituality and the amulets worn around his neck. He was then challenged to prove their strength.'

Lieutenant General Mitrak said the injured man had a 20cm (8in) long wound in his head and a large knife was recovered from the scene.

The monk can be seen holding what looks like a foot long blade while his victim is bleeding on the ground

Paramedics and police rushed to the scene to takeover from the brave efforts of the English-speaking bystander

He added: 'The foreign man was very brave to help the victim. His courage helped to save him from losing more blood until paramedics arrived.

'Witnesses at the scene have described an argument between the monk and the victim.

'We do not know if the attacker was a real monk or his background.

'We will check CCTV and interrogate both parties to find the full story and prosecute the attacker.'