Chinese e-commerce giant Alibaba Group announced Monday that one of its websites was hacked on Friday and Saturday and the police were investigating.

Servers of Alibaba's foreign wholesale marketplace, Aliexpress, in Hangzhou, east China's Zhejiang Province, and in the United States were hacked constantly on April 16 and 17, said Wu Hao, head of public relations at Alibaba Group.

The website, still in the testing phase, hosted the sale of Chinese goods in bulk to American buyers, said Wu.

"Our clients' information was not disclosed or stolen. But some users could not access our website at some point," said Wu.

The company did not say where the attacks originated, but Wu told Xinhua that they believed the hackers might come from overseas trade protectionist groups or Alibaba's rivals.

Wu said Aliexpress, which had been in the test period since Aug. 6, 2009, would officially start operations, although no timetable had been set.

A spokesman for the Municipal Public Security Bureau of Hangzhou, where Alibaba is based, said police would investigate the incident.

Alibaba Group is an online business company, engaging in business-to-business international trade and retail sales. It was founded in 1999.