Ian Murdock, the Linux programmer who died under mysterious circumstances after claiming he was beaten by police, hanged himself.

The cause of his death last December has remained unreleased until CNNMoney obtained the autopsy report from the San Francisco medical examiner's office.

The autopsy records also note his body was covered in bruises -- on his chest, abdomen, back, arms and legs.

Murdock, 42, was a celebrated pioneer in the technology sector. He had served as an executive at Sun Microsystems, Salesforce (CRM) and software company Docker.

He was best known for his 1993 creation of Debian, the second-most popular version of the free operating system Linux. Debian is still used to run electronic gadgets all over the world -- from Google's powerful computer servers to the International Space Station. Murdock's first name was the "Ian" in "Debian."

Murdock played a monumental role in defining the spirit of "open source" software -- collaborative projects that are freely shared, created and maintained. He wrote "The Debian Manifesto" in 1994. That helped model the definition of open source years later.

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Murdock's death last year was alarming because he took to Twitter to accuse police of assaulting him.

"The police here beat me up for [knocking] on my neighbor's door.. they sent me to the hospital," he wrote. "They followed me home... then they pulled me out of my house and did it again."

The San Francisco Police Department acknowledged to the local newspaper that officers arrested Murdock on Dec. 26, late on a Saturday night, for trying to break into his neighbor's home while drunk. Officers said Murdock banged his own head against the metal cage inside the police car. They arrested him again a few hours later for again banging on his neighbor's door.

On Sunday, Murdock started detailing his experience online.

"They beat the s--- out of me twice, then charged me $25,000 to get out of jail for battery against THEM," he tweeted. "I'm committing suicide tonight.. do not intervene as I have many stories to tell and do not want them to die with me."

His messages were angry, erratic and at times racist.

Several friends and acquaintances who saw these messages online called San Francisco police and asked them to stop by Murdock's home to prevent him from killing himself, according to the medical examiner's report.

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When a police officer showed up the tech entrepreneur's home Monday morning, the doors were locked, according to the records. But inside, he could see Murdock's naked body lying face down on the stairs -- and a vacuum electrical cord wound tightly around his neck, according to the medical examiner's report. The vacuum cleaner was positioned at the top of the stairs, behind the railing.

Adam Hellman, the death investigator, found "no obvious signs of external trauma or foul play."

His neighbor told investigators that Murdock had recently broken up with his girlfriend and was being evicted from his home at the end of the month, according to the report.