China took fresh steps to clamp down on HNA Group Co. by banning it from conducting some financial transactions with an insurance unit for a half year, potentially drying up a source of funding for the debt-saddled conglomerate.

HNA’s Bohai Life Insurance Corp. failed to report some related-party transactions, made some untimely disclosures and had a compensation system that didn’t meet regulatory requirements, the China Insurance Regulatory Commission said on its website late Wednesday. That led the regulator to order the insurer to stop direct and indirect transactions—including loans and financial aid—with HNA companies for six months.

HNA and Bohai Life representatives didn’t respond to requests for comment. The CIRC didn’t immediately reply to a fax seeking further details about which related-party transactions were not reported by Bohai.

Corporate filings seen by Bloomberg show Bohai Life has been a source of financing for HNA, which has been raising billions of dollars through shadow-banking products that are more expensive than traditional forms of borrowings but also less regulated.

It’s the latest setback for HNA, which has been under mounting scrutiny this year after a debt-fueled shopping binge made it stand out as one of the country’s top buyers of global assets, putting the company in the crosshairs of a government that’s clamping down on capital outflows. The company has also faced questions from overseas regulators about its ownership amid allegations—repeatedly denied by HNA—that it’s tied to powerful Communist Party officials.

HNA, which has announced more than $45 billion in acquisitions since 2015 including large stakes in Deutsche Bank AG and Hilton Worldwide Holdings Inc., is showing signs that its debt-fueled expansion is catching up with the company. The group’s interest expenses more than doubled during the first half to about $2.4 billion, more than any company outside of the U.S. and Brazil, according to data compiled by Bloomberg as of Thursday.

HNA’s Bohai Financial Investment Holding Co., the biggest shareholder of closely held Bohai Life, fell as much as 1 percent in Shenzhen trading on Thursday.

One example of Bohai Life’s dealings with the group involved combined investments of 1 billion yuan ($152 million) in 2016 and 2017 into trust products—offering annual returns of 8.8 percent—linked to an affiliate called Changjiang Leasing, with the proceeds going to HNA Capital to pay back loans, according to Bohai Life’s website.

The CIRC, which also disclosed temporary bans to other local insurers on Wednesday, has been tightening scrutiny of the industry this year, seeking to prevent the eruption of any systemic risk as officials crack down on investments they deem hazardous. Anbang Insurance Group Co. Chairman Wu Xiaohui has been detailed by Chinese authorities since June.

HNA has also been under scrutiny from outside of China. Last month, the Swiss Takeover Board asked the conglomerate to explain its ownership changes, while U.S. officials are examining its proposed purchase of Anthony Scaramucci’s SkyBridge Capital.