HANGZHOU - Chinese e-commerce giant Alibaba, which is preparing for its US initial public offering (IPO), announced on Friday that it called the police after being blackmailed by a media institution.

According to a statement issued by the company, a media outlet had requested that Alibaba pay $300,000 in exchange of a research report against the company.

The company is currently in the quiet period before its IPO, which has been postponed until September, according to latest reports.

The research is allegedly based on negative reports from a domestic weekly and comments by individuals online, the statement said.

Police in Hangzhou city, where the company is based, accepted the case on Monday.

Alibaba welcomes supervision from the mass media, but it will not tolerate acts that go beyond the legal boundaries, said Alibaba's founder and chairman Jack Ma.

The statement did not disclose the media institution's name, but insiders speculated it referred to a Guangzhou-based semi-monthly business magazine.

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