FILE PHOTO: A person walks past by a gate with a sign of Vanke at a construction site in Shanghai, China, March 21, 2017. Picture taken March 21, 2017. REUTERS/Aly Song/File Photo

SHANGHAI (Reuters) -Chinese state-backed property developer Vanke's bonds tumbled on Wednesday, reigniting market concerns about the extent of potential central government support for the crisis-hit sector.

Several of Vanke's yuan bonds fell more than 20% in early trade, leading to trading suspensions on the company's five exchange-traded bonds, the Shenzhen Stock Exchange said.

Deflationary pressures have persisted in China since the COVID-19 pandemic, weighing on consumer and business confidence. These pressures have become entrenched, most notably in housing.

New home prices fell at the fastest monthly pace in a year in October, highlighting persistently weak demand.

Vanke, one of China's best-known household names and one-third owned by Shenzhen Metro Group, faces renewed market scrutiny.

Markets are replaying a pattern from earlier this year, said Yao Yu, founder of Shenzhen-based credit research firm RatingDog. He said markets had priced for Vanke not to be able to meet debt repayment obligations, sparking a steep sell-off before rebounding on signs of state support.

"Now, market rumors suggest Shenzhen has sought help from Beijing, leaving two scenarios — no rescue or central backing," Yao said.

Vanke's yuan bond due in March 2027 was traded at 60 per 100 par value as of midday, down from 80 at the open, a nearly 30% drop.

The bond traded around 40 at the end of last year before a sharp rebound early this year on optimism over potential state support.

Earlier this month, Vanke said Shenzhen Metro agreed to provide loans of up to 22 billion yuan ($3.09 billion), a stock exchange filing showed.

While authorities rolled out a series of key measures in the second half of 2024 to support the market, large-scale new stimulus has been withheld this year. Recent policy steps have mainly reaffirmed existing commitments.

Vanke shares listed in Hong Kong fell nearly 3%, while its onshore shares slipped to their lowest since 2008.

(Reporting by Shanghai Newsroom; Editing by Himani Sarkar and Jacqueline Wong)