A San Francisco man who created the online drug-selling site Silk Road was sentenced Friday to life in prison by a judge who cited six deaths that resulted from drugs bought on his website and five people he tried to have killed.

U.S. District Judge Katherine Forrest told Ross Ulbricht he was a criminal even though he doesn't fit the typical profile — he has two collegiate degrees — and she brushed aside his attempt to characterize the business as a big mistake.

"It was a carefully planned life's work. It was your opus," she said. "You are no better a person than any other drug dealer."

Forrest said the sentence was necessary to show others who might follow in his path that there are "very serious consequences." She also ordered $183 million forfeiture.

Ulbricht, 31, was convicted in February of operating the site for nearly three years from 2011 until his 2013 arrest.

Prosecutors say he collected $18 million in bitcoins through commissions on drug sales on a website with thousands of listings under categories like "Cannabis," ''Psychedelics" and "Stimulants." They said he brokered more than 1 million drug deals worth over $183 million while he operated on the site with the alias Dread Pirate Roberts — a reference to the swashbuckling character in "The Princess Bride."

The judge said Ulbricht's efforts to arrange the murders of five people he deemed as threats to his business was proof that Silk Road had not become the "world without restrictions, of ultimate freedom" that he claimed he sought.

Forrest said she was "blown away in fury" at the "breathtakingly irresponsible" Internet postings of a doctor who advised customers on Silk Road about the effects of various drugs.

Prosecutors cited at least five deaths traced to overdoses from drugs bought on Silk Road, and a parent of two of the victims spoke in court.

Before the sentence was announced, a sniffling and apologetic Ulbricht told Forrest he's a changed man who is not greedy or vain by nature.

"I've essentially ruined my life and broken the hearts of every member of my family and my closest friends," he said. "I'm not a self-centered sociopathic person that was trying to express some inner badness. I do love freedom. It's been devastating to use it."

His hands folded before him, Ulbricht was stoic as the sentence was announced. As he left the courtroom, he carried with him photographs of those who died as a result of drugs purchased on Silk Road.