China imposed a fine of 18.2 billion yuan ($2.8 billion) on Alibaba Group after an anti-monopoly probe, part of a regulatory crackdown that has raised concerns about the future of Jack Ma¡¯s tech empire.

The penalty is equivalent to 4% of Alibaba¡¯s domestic sales in 2019, China¡¯s State Administration for Market Regulation said in a statement on Saturday.

Alibaba will also be required to implement ¡°comprehensive rectifications,¡± including strengthening internal controls, upholding fair competition, protecting businesses on its platform and consumers¡¯ rights, the regulator said. The company will be required to submit reports on self-regulation to the authority for three consecutive years.

Alibaba has been under mounting pressure from Chinese authorities since its founder Ma spoke out against China¡¯s regulatory approach to the finance sector in October. Those comments set in motion an unprecedented regulatory offensive, including scuttling plans for Ma¡¯s Ant Group Co.¡¯s $35 billion initial public offering.

The company said it ¡°sincerely¡± accepted the penalty and will comply.

¡°We will intensify our operation according to the law, further strengthen the construction of the compliance system based on innovation and development, and better fulfill social responsibility,¡± Alibaba said on Saturday.