Truong Van Cam, also known as Nam Cam, has been portrayed as Vietnam's version of the Godfather.
Nam Cam was arrested in 2001
The 56-year-old mafia boss is said to have been at the heart of a 15-year killing spree in Ho Chi Minh City - as well harbouring fugitives and being involved in gambling, bribery and prostitution rackets.
His trial for murder in the city's People's Court has been one of the largest in Vietnam's history.
His execution by firing squad has brought an abrupt end to a violent but colourful life.
Born to a poor family in the former Saigon in 1947, Nam Cam's first brush with the law came at the age of 15, when he was arrested for killing a man during a fight.
He spent more than two years in jail, and then joined the South Vietnamese army in 1966.
Charges against Nam Cam
Organising illegal emigration
At the end of the Vietnam war, he is said to have reverted to a life of crime in Ho Chi Minh City.
He was arrested again in May 1995 for his criminal dealings, but was released early following an intervention by senior officials alleged to be on his payroll.
The father of eight children, Nam Cam is known throughout the city's underworld as an inveterate gambler and womaniser.
In his heyday he was considered one of the most powerful figures in Vietnam.
He certainly seems to have had friends in high places.
More than 150 people went on trial with him - some of them high-ranking Communist Party officials and members of the police.
In fact his connections were so close to the local police department that officers from other provinces were sent in to arrest him when the authorities finally decided to swoop in December 2001.
Among the more sensational charges he faced was the alleged assassination of a rival gang boss, Dung Ha.
At one stage the two worked together, with Dung Ha joining forces with Nam Cam in the hope he would get her to run his underground gambling dens.
But the pair fell out when Dung Ha tried to create her own gang, and she once sent a box full of rats to one of his restaurants to annoy him, Vietnamese state media reported last year.
In return Nam Cam is said to have ordered her death. Dung Ha's body was found shot through the head in October 2000.