Changfa (Daniel) Kao, a former business associate of the accused, said Wang threatened to kill both of the now deceased men in phone conversations he'd sat in on.
Both Mr Wu and Mr Zhong had been former friends and business associates of Wang, but the relationships soured as the pair were allegedly owed money by Wang from property deals.
Mr Kao said he listened on speakerphone to a conversation where Mr Zhong asked for $90,000 allegedly owed to him from Wang.
When Mr Zhong said he would take legal action if he didn't see the money, Wang threatened "I will kill you'', he said.
During cross examination, Mr Sutcliffe suggested Mr Zhong was actually owed money by two other business associates. When asked about this, Mr Kao said he didn't know the details of the business agreement.
Mr Kao said he also heard Wang threaten the second of the deceased, Mr Wu, during another phone conversation on speakerphone. He has not yet been cross-examined on this conversation.
The pregnant daughter of one of the deceased, Ying Yang (Jade) Zhong, also took to the stand this morning.
She said she had been involved in a property deal with Wang which had gone sour. She bought a house in New Lynn, Auckland, and Wang organised a tenant for the house, she said.
However the tenant never paid rent and served a trespass notice against her when the money was asked to be paid, she said.
The tenant was removed and the issue had since been resolved after legal action, she said.
Her father became friends with Wang after he first met him in 2008. The pair often went fishing and hunting together, and he attended karaoke parties thrown at Wang's house, she said.
After Wang found out her father's financial position, Ms Zhong said Wang convinced her father to give loans to Wang's friends, who were to pay back the amount plus interest.
The loans were not paid back, she said.
On the day of her father's death, he told her he was going round to Wang's house, she said. She asked him not to go.
"He did not tell me exactly the plan but he did mention that Michael has a paper.
"He would not allow Michael to go there alone because he knew how dangerous it could be. He was not scared but he was aware of how dangerous [Wang] could be.''
At the time of his death, Mr Zhong had sought legal help and "everything was in progress'' to reclaim money allegedly owed by Wang.
The trial continues.