Billionaire Richard Liu, founder and chief executive officer of JD.com Inc., attends the Wall Street Journal DLive Asia Conference in Hong Kong, China, on Friday, June 9, 2017. The conference runs from June 8 to 9.

Minnesota prosecutors will not charge the billionaire chief executive officer of China's JD.com, Richard Liu, after he was accused of rape by a University of Minnesota student during a recent U.S. visit, authorities said on Friday.

Hennepin County Attorney Michael Freeman said there were "profound evidentiary problems which would have made it highly unlikely that any criminal charge could be proven beyond a reasonable doubt."

In a statement, Freeman said that after an investigation by Minneapolis police and a review by four senior sexual assault prosecutors, it was clear his office could not meet its burden of proof, and therefore could not bring charges.

"Because we do not want to re-victimize the young woman, we will not be going into detail," Freeman said.

The 45-year-old Liu, who grew JD.com from a humble electronics stall to an e-commerce giant with 2017 net revenues of $55.7 billion and maintains tight control of the company, was released without charge about 17 hours after he was arrested on Aug. 31.

He quickly returned to China, where he has continued to run the company. His representatives have maintained his innocence after the woman from China studying at the University of Minnesota accused him of rape.

Liu said in a social media post he felt "utter self-admonishment and regret" for the "enormous pain" his "actions on that day" caused his family, especially his wife, internet celebrity Zhang Zetian.

"I immediately confessed to her the truth, and hope she can accept my most sincere apologies," he said in a statement on the Weibo platform.

Liu said the decision by prosecutors not to press charges proved that he had not violated any laws "from to start to finish."

He said he had been unable to defend himself earlier despite "misleading information" and could not respond to comments in social media and news reports because he did not want to obstruct the investigation and judicial process.

JD.com shares extended gains on Friday after news spread of the decision not to prosecute, and closed up 5.9 percent.

The case has attracted extreme interest in China. Liu could have faced up to 30 years in prison under Minnesota law if convicted of first-degree criminal sexual misconduct.