His weapon was not a knife or a gun. It was his bare hands.
In Vietnam, Nguyen Hoang Minh, 20, was arrested on Feb 23 for killing a motorbike taxi rider with a jiujitsu move.
Vietnamese news website Tuoi Tre News also said Minh's father is a Singaporean and that Minh was a member of the Jiujitsu Association of Singapore.
But a spokesman for the association said it has no record of Minh.
Mr Joseph Tan, 62, told The New Paper on Sunday: "His name does not ring a bell and our records do not match him at all."
Reports said Minh was riding pillion on the motorbike of Mr Luu Thanh Son, 61, in Ho Chi Minh City's District 2 at around 2.10am last Tuesday when he attacked the rider and robbed him.
A video, uploaded by another Vietnamese news website Vo Thuat on Friday, showed Minh attacking Mr Son while the pair were still on the bike.
With both his hands, the pillion passenger grabbed on to the rider's neck and did not let go despite the rider's clear struggles to break free.
The pair eventually ended up on the ground and the rider stopped moving.
The pillion passenger then got up and started the motorbike to leave but bent over to his left to pick up what Tuoi Tre News said were the victim's handphone and wallet.
Mr Son was reportedly found dead later in the day by residents in the area.
Minh is believed to be in police detention.
The incident apparently ensued after Mr Son took a longer route to send Minh home that night after a drinking session.
Mr Son demanded that Minh pay him VND100,000 (S$6.30) - about three times the originally agreed price of VND30,000.
According to Tuoi Tre News, Minh's father and Vietnamese mother are divorced. He now lives with his mother and a sibling in Vietnam.
The report added that he is a jiujitsu expert and once won a silver medal during an international tournament held in Singapore.
Mr Tan condemned the use of jiujitsu to hurt and kill, saying that it should be used only for self-defence.
"It is never to kill a person. When we defend ourselves with jiujitsu, we immobilise the person and then we call someone like the police to help."
This article was first published on February 28, 2016.
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