Chinatown murder victim in a triad: court

A gambling addict accused of the fatal daytime stabbing of a 64-year-old grandfather feared the "loan shark" was a member of a triad, a court has heard.

Defence barrister Jarred Williams said waiter Fai Sing Yiu, 60, feared for his life and acted in self-defence when he stabbed Alan Wong to death in Chinatown's Golden Square carpark on October 29, 2014.

Yiu is on trial in the Victorian Supreme Court after pleading not guilty to murder.

Mr Wong, a father of four daughters, was owed $24,000 by Yiu and had called him to ask about the money, the court heard.

Mr Williams said Yiu believed Mr Wong was part a gang called the 14K Triad Society, which is why he armed himself with a knife when he went to meet with Mr Wong.

"Mr Yiu armed himself with a knife in fear of being attacked by Mr Yiu or one of his criminal associates," Mr Williams said.

Crown prosecutor Sharn Coombes says Yiu killed Mr Wong, who has been living in Australia illegally since the mid-80s, to clear himself of debt.

Mr Wong had spent the morning of his death visiting his grandchildren and delivering biscuits to his daughter, Ms Coombes said.

He then went to meet Yiu, who had missed his last three debt repayments, the court heard.

Mr Wong, who had had two heart attacks, used a walking stick, but left it in the car for the meeting, Ms Coombes said.

Yiu led Mr Wong to a carpark where CCTV footage shows he reached into his pocket and pulled out a knife.

Wong, who was carrying a bag of heart medication, can be seen putting up his hands, Ms Coombes said.

The men fought and Yiu stabbed Mr Wong eight times.

Ms Coombes said he died from a stab wound to the heart.

Yiu rendered no help and told a witness who saw him flee the carpark that Mr Wong had "tried to commit suicide", Ms Coombes said.

"Mr Yiu owed a large amount of money to Mr Wong," she said.

Mr Williams said there is no dispute Yiu killed Mr Wong, but the focus was his state of mind at the time.

"This is not a whodunnit," Mr Williams said.

"The focus of this trial turns on why Mr Yiu did what he did."

The trial continues.