A Russian man accused of hacking LinkedIn Dropbox , and Formspring made his first appearance in federal court on Friday.

In a brief hearing before a federal magistrate judge in San Francisco, Yevgeniy Nikulin pleaded not guilty to illegally accessing computers belonging to those companies in 2012.

Nikulin was arrested on October 5, 2016, but he was only very recently extradited from the Czech Republic to the United States. In the Czech Republic, Nikulin's attorneys and the Russian government attempted to get him sent back home to face significantly lesser criminal charges dating back to 2009.

"Computer hacking is not just a crime, it is a direct threat to the security and privacy of Americans," said Attorney General Jeff Sessions in a statement sent to reporters.

"In this case, the defendant, a Russian national, is accused of breaking into the computer system of several important American companies using stolen identities, and potentially gaining access to the personal information of millions of Americans. This is deeply troubling behavior once again emanating from Russia. We will not tolerate criminal cyber-attacks and will make it a priority to investigate and prosecute these crimes, regardless of the country where they originate."

In the case of LinkedIn, more than 117 million accounts were affected. At Dropbox, more than 68 million people were hit.

According to Bloomberg, Nikulin's federal public defender told the court that he "has a number of medical issues and is hoping to go to the hospital."

US Magistrate Judge Jacqueline Corley set Nikulin’s next hearing for April 2, 2018.