Kevin Mitnick, the hacker who left the authorities dead, has died at the age of 59

Kevin Mitnick, a reformed hacker who was once one of the most wanted computer criminals in the United States, died Sunday, according to a statement shared Wednesday by a cybersecurity training company he co-founded and a funeral home in Las Vegas. He was 59 years old.

A spokeswoman for the organization, Kathy Watman, confirmed his death know 4.

The cause was complications from pancreatic cancer. He was undergoing treatment at the University of Pittsburgh Medical Center after being diagnosed more than a year ago, according to King David Memorial Church and Cemetery in Las Vegas.

After serving a prison sentence for computer crimes, he was released from prison in 2000 and began a new career as a security consultant, writer, and public speaker.

Mr. Mitnick is best known for his crimes during the 1990s that included stealing thousands of data files and credit card numbers from computers across the country. He has used his skills to hack his way into the nation’s phone and cell networks, and sabotage the computer systems of government, corporations, and universities. Investigators at the time named him the “most wanted” computer hacker in the world.

In 1995, after more than two years of manhunt, Mitnick was arrested by the FBI and charged with illegal use of a telephone access device and computer fraud. He allegedly had access to multi-million dollar corporate trade secrets. “He was a very big threat,” Kent Walker, a former assistant US attorney in San Francisco, said at the time.

In 1998, while Mitnick was awaiting sentencing, a group of supporters took over The New York Times website for several hours, forcing it to shut down.

The following year, Mr. Mitnick pleaded guilty to computer and wire fraud as part of an agreement with prosecutors and was sentenced to 46 months in prison. He was also prohibited from using a computer or mobile phone without the permission of the probation officer for three years after his release.

Mr. Mitnick grew up in Los Angeles as the only child of divorced parents. He moved around a lot and was kind of a recluse, studying magic tricks, according to his 2011 memoir “Ghost in the Wires.” At the age of 12, Mr. Mitnick figured out how to ride the bus freely using a $15 punch card and blank tickets fished out of a dumpster, and by high school he developed an obsession with the inner workings of switches and phone company circuits.

By the age of seventeen, he was hiding in various company computer systems and, eventually, had his first encounter with the authorities for those activities; The beginning of a decades-long cat-and-mouse game with law enforcement.

In his memoirs, Mr. Mitnick disputes many of the accusations against him, including that he hacked into government computer systems.

Mitnick also claimed that he ignored credit card numbers he obtained in his pursuit of the code. “Anyone who loves to play chess knows that it is enough to defeat your opponent. You do not have to pillage his kingdom or confiscate his assets to make it worthwhile,” he wrote in his book.

Among the survivors is Mr. Mitnick’s wife, Kimberly Mitnick, who is pregnant with her first child, according to the obituary.

A full obituary is coming.