LOS ANGELES (CBSLA.com) — Actor Charlie Sheen publicly revealed his HIV diagnosis on Tuesday.

During a sit-down interview with Matt Lauer on the “Today” show in New York, the former “Two and a Half Men” star admitted he was diagnosed four years ago after he experienced a cluster of headaches.

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“I thought I had a brain tumor,” Sheen said. “I thought it was over. After a battery of tests and spinal taps, [my doctors] said this is what’s going on. I am here to admit that I am in fact HIV-positive.”

According to the actor, all of his sexual partners have been notified about his diagnosis, including ex-wives Denise Richards and Brooke Mueller.

“It’s a hard three letters to absorb,” Sheen said.  “It’s a turning point in one’s life.”

Meanwhile, his ex-girlfriend, Bree Olsen, is claiming she was never told of his diagnosis, according to Entertainment Tonight.

The 50-year-old claims he has used protection with all but two of his partners, whom were made well aware of his condition, since learning that he contracted the virus.

The state of California has the ability to charge an individual with a felony in the event that the person had knowingly infected someone with HIV.

“He put my life in jeopardy, along with hundreds, or potentially thousands of other women’s lives,” Olsen said.

However, as some experts suggest, a lawsuit against Sheen would be difficult to win.

“You would have to prove liability and you’d have to prove damages,” CBS2 Legal Analyst Steve Meister said. “That means he would have had to have knowledge of his own condition, and withheld that knowledge from a partner, which he disputes, and then the partner would have to have suffered damages.”

“No one’s going to sue for the cost of an AIDS test.”

She maintains he has never knowingly transmitted the disease, and at this time, he remains unsure how he contracted the virus.

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Prior to his announcement this morning, rumors regarding his health publicly swirled among the tabloids.

According to Sheen, he is a victim of betrayal and extortion as he paid people to keep his diagnosis quiet.

The actor could not recall exactly how many people have been paid, but said “I’ve told enough [people] that I’ve trusted to be in the position I am today,” citing millions have been spent to cover his secret.

“I have to put a stop to this onslaught and barrage of attacks of sub-truths and very harmful stories that are about threatening the health of so many others, which could not be farther than the truth,” Sheen explained. “I think I release myself from this prison today.”

“My trust turned to their treason,” he added.  “What people forget is that’s money they are taking from my children.”

During the interview, Sheen confirmed one incident of alleged extortion occurred when a prostitute captured a cell phone image of medication found inside his bathroom after spending the day at his home.

Sheen has publicly struggled with substance abuse problems for several years.

In 2011, he made headlines during what appeared to be a public meltdown. The incident subsequently led to the parting of his role on the CBS sitcom “Two and a Half Men.”

The actor has admitted to heavy drinking, drug use and making bad choices about who he was associating with.

He told Lauer: “I was so depressed by the condition that I was in that I was doing a lot of drugs. I was making really bad decisions. That part I own 100 percent.”

“I have a responsibility now to better myself and to help a lot of other people,” said Sheen. “Hopefully with what we are doing today others may come forward.”

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Moving forward, Sheen has plans to act in a television series along with several films.