A top Vietnamese property tycoon went on trial Tuesday accused of cheating thousands of investors in a $355 million bond scam, in the nation's latest criminal case targeting high-flying business leaders.

Vietnam has embarked on a sweeping graft crackdown in recent years, with corrupt officials and senior business figures among 4,400 people indicted in more than 1,700 cases since 2021.

Do Anh Dung, head of the Tan Hoang Minh group, which specialises in luxury offices and apartments, went on trial in Hanoi on Tuesday alongside his son Do Hoang Viet and 13 others on fraud charges.

They are accused of illegally acquiring $355 million in a bond sale to 6,630 investors -- all of whom have been invited to attend the trial, which is expected to last around three weeks.

Thousands took up the invitation and poured into the Hanoi People's Court, where a large viewing area was set up with CCTV to allow the victims to follow proceedings.

According to previous state media reports, by January 2022 the Tan Hoang Minh group was struggling with debts of some $810 million because of stalled projects and the impact of the COVID-19 pandemic.

The defendants sold bonds to raise capital, promising investors high returns, but embezzled the $355 million raised, the VNexpress news site reported, quoting a copy of the indictment.

The father and son have already repaid the $355 million, according to state media.

One victim who attended court told AFP she invested $20,000 of family savings in the bonds and was glad the authorities had brought the case.

"I have not received anything. I feel so stupid investing in these bonds," 47-year-old office worker Phuong, who gave only one name, said.

"Now I really hope they give the money paid by the boss of Tan Hoang Minh to people like us."

Thuy, 72, said she invested her life savings of $40,000 in the bonds.

"I really don't know whether I will get all my money back," she told AFP.

"I don't know whether I want them to be jailed for long or what. I just want my money back."

In the country's biggest ever fraud case, Truong My Lan, chairwoman of the Van Thinh Phat property development group, is currently on trial in Ho Chi Minh City accused of embezzling $12.5 billion.

The trial of 86 people, including former senior state bank and government officials, is expected to end in late April.