To do so, it relied on selling Chinese customers short-term investment products that promised hefty payouts. The products are sold by Anbang and many other Chinese companies, but they disclose little about the underlying investment. Many customers assume the investments are backed by the government even though they are not, putting pressure on officials to make sure investors are paid with government money if the investments go south.

In the case of Anbang, both the company and government officials have said that the money given to it by small investors is sound. Anbang said in a statement on its website that its business operations were stable and that it has “sufficient cash flow to fulfill its policy commitments to all Anbang customers and ensure that the legitimate rights of its policyholders are not lost.”

After acquiring the Waldorf Astoria, Anbang tried a number of prominent global deals, including an unsuccessful campaign to buy Starwood Hotels and Resorts Worldwide and a bid to buy a stake in a Manhattan office building partly owned by Jared Kushner’s family company. The deal with Mr. Kushner, President Trump’s son-in-law, was eventually abandoned after it was covered by the news media.

Mr. Wu’s fortunes took a turn for the worse last year when the government, wary about rising levels of debt, began to scrutinize its big deal makers. That led to public criticism of some of those companies and restrictions on capital outflow. On top of that, Anbang was never able to explain fully who its shareholders were to American regulators, who were pressing the company on its ownership structure.

China is now trying to rein in the growth of its wealth management products industry, fearful that excessive levels of debt could destabilize its economy, the world’s second-largest behind that of the United States. The scrutiny on Anbang roughly coincided with the removal of the commissioner of the China Insurance Regulatory Commission a year ago. On March 12, the Chinese government said it would merge banking and insurance regulators in an effort to close regulatory loopholes.

Prosecutors in China say that Mr. Wu concealed his control of companies that he then used to hold shares of Anbang Insurance and Anbang Group. Using one of Anbang Group’s subsidiaries, Anbang Property & Casualty Insurance Company, as a funding platform, he ordered the development of investment-type insurance products.

According to prosecutors, Mr. Wu led the design of the products and instructed the company to make false financial statements and marketing brochures. By doing that, he managed to get approval from the insurance regulatory agency to raise funds from the public.

By Jan. 5, 2017, the company had sold $116.5 billion of products, far more than the amount the government had approved. Some of that money was then moved to the companies that Mr. Wu controlled. Those funds were used to invest, to repay debts and for personal spending, according to prosecutors. Mr. Wu said the capital increase was from his self-owned funds.