Yihaodian promises next-day delivery for more than 180, 000 products, including groceries, electronics and clothing.

WSJ: Chinese Online Retailer Yihaodian Probes Possible Security Breach

She said the company added measures to boost security on Yihaodian.com, including the addition of account-verification codes.

WSJ: Chinese Online Retailer Yihaodian Probes Possible Security Breach

It recently bought a stake in Yihaodian, a fast-growing online retailer of groceries, consumer electronics and apparels.

FORBES: China Just One Reason Wal-Mart Stock Gets To $75

Wal-Mart in February said it plans to increase its stake in Yihaodian to 51% from 18%, pending government approval.

WSJ: Chinese Online Retailer Yihaodian Probes Possible Security Breach

They reached an agreement to increase its investment from around 20% to 51% in Yihaodian, an e-commerce website in China.

FORBES: Wal-Mart Expanding In China, Possibly Returning To Russia

Wal-Mart also acquired a 51% stake in Yihaodian, a China e-commerce retailer, to improve its online sales in the region.

FORBES: Wal-Mart's Slow U.S. Growth Needs International Muscle To Drive Earnings

Yihaodian operates next-day delivery service for essential daily goods at competitive prices.

FORBES: China Just One Reason Wal-Mart Stock Gets To $75

Yihaodian, Wal-Mart's online arm in China, is working with local public-security officials to investigate the breach, a spokeswoman for the Shanghai-based company said Monday.

WSJ: Chinese Online Retailer Yihaodian Probes Possible Security Breach

The three and a half year old privately held Yihaodian sells over 180, 000 products on line, and has a strong market share in the online grocery market.

FORBES: Wal-Mart Expanding In China, Possibly Returning To Russia

Yihaodian is no joke.

FORBES: Wal-Mart Expanding In China, Possibly Returning To Russia