Adrian Lamo, a well-known hacker, has died at 37.
The hacker is best known for high-profile hacks of companies like Microsoft, and later for turning in Chelsea Manning to the FBI after receiving leaked documents from her.
It's unclear how Lamo died. The coroner for Sedgwick County, Kansas, where Lamo lived, confirmed his death but didn't provide further details, according to CNET sister site ZDNet.
In the Facebook group "2600 | The Hacker Quarterly," Lamo's father, Mario Lamo, posted a tribute to his son on Friday.
"A bright mind and compassionate soul is gone, he was my beloved son," the father wrote.
Lamo, a Colombian-American who lived in Wichita, Kansas, was once nicknamed the "homeless hacker" because he would drift across the US on Greyhound buses, finding shelter with friends or in vacant buildings.
He was at the center of an FBI chase in 2003, where agents staked out his family's home in Sacramento, California, for five days until Lamo turned himself in. He'd been wanted after using public internet connections to break into corporate networks and websites, including gaining unauthorized access to The New York Times, Microsoft and LexisNexis.
He would edit news articles on Yahoo and use LexisNexis to search for owners of undercover police cars. After Lamo turned himself in, the notorious hacker was sentenced to six months of house arrest, along with 2 years of probation and a $60,000 fine.
Other websites that he breached thanked him for the uninvited penetration testing. He once bragged about breaking into Excite@Home, a website that no longer exists, and answering help desk requests from users who'd been ignored.
Lamo's name resurfaced in the news after he turned in Manning to the US government in 2010, a move that elicited multiple online death threats. Manning was arrested because of Lamo's intel, and sentenced to 35 years in prison. She was released last year after President Barack Obama granted her clemency in 2016.
The leaked military documents surfaced on WikiLeaks, which Julian Assange runs.
The WikiLeaks founder reacted to Lamo's death by insulting him on Twitter, calling the hacker a "serial FBI snitch," among other names.
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