Hundreds of photos and videos of naked women used as collateral for loans on a Chinese online lending service have leaked onto the web, highlighting regulatory problems in the fast-growing peer-to-peer marketplace.

A 10-gigabyte file posted on the internet exposed the personal details of more than 160 young women who were asked to provide the explicit material to secure money through online lending platform Jiedaibao.

Launched by JD Capital (Shanghai: 600053.SS - news) in 2015, Jiedaibao allows lenders to operate anonymously but requires borrowers to reveal their real names when making transactions.

Loan amounts and interest rates can be customised to meet the needs of users -- often people who have a hard time accessing loans through more traditional financial institutions, like banks.

Interest on the "nude loans" reached an astonishing 30 percent a week, according to the Global Times newspaper.

Lenders told female borrowers that if they failed to repay the loans, their nude photos would be sent to their families and friends, whose information was also required for some transactions, the article said.

Material in the file put on the web last Wednesday showed some borrowers also promised to repay loans with sexual favours, according to screen captures posted on social media websites.

In a statement on its official Twitter (Frankfurt: A1W6XZ - news) -like Weibo account, Jiedaibao said it had tracked down the accounts of several borrowers through photos and ID information circulated online and had frozen the suspected lenders' accounts.

"The 'nude loans' deals were mainly initiated and completed offline, and Jiedaibao only played the role of a money transfer platform in the deals," the statement said.

The case is not the first time online P2P (Shanghai: 600696.SS - news) businesses have been connected to potentially embarrassing photos.

In November, Alipay, the payment platform of Chinese e-commerce giant Alibaba (Berlin: AHLA.BE - news) , was criticised after a set of photos showing female users in seductive poses was leaked on social media.

The photos were originally posted in Alipay's newly launched social media feature called Circles, which allows only women to post photos, and had obscene comments from male users.

China has nearly 2,600 platforms described as P2P businesses, according to one industry estimate, with transactions valued at around $150 billion last year.

Beijing has been particularly worried about P2P lending and in August it tightened regulations by setting a borrowing limit of one million yuan for individuals.

It also required platforms to supply and verify the information of both borrowers and lenders, and provide credit assessment, financial consulting and conflict resolution services.