UPDATE, 6 AM with video: “I’m here to admit that I’m in fact HIV positive,” Charlie Sheen told Matt Lauer on NBC’s Today this morning. “I have to stop this onslaught of attacks and sub-truths and very harmful and mercurial stories about the threatening the health of so many others which couldn’t be further from the truth.”

Sheen said he first realized something was wrong with a cluster of severe headaches. “I thought I had a brain tumor, thought it was over,” Sheen said. After a battery of tests, he was told of his condition. “It’s a hard three letters to absorb; it’s a turning point in one’s life,” Sheen told Lauer.

NBC News said yesterday Sheen was going to “make a revealing personal announcement” in this morning’s live interview with Lauer. The news division provided no other details but, moments after it alerted the media, the National Enquirer blasted out headlines about Sheen having “hid…HIV virus for 4 years.” The back-to-back headlines brought to a high boil days of speculation as to who was the Hollywood actor referenced in last week’s blind reports about an unnamed a “Hollywood superstar” who has for years been hiding his HIV battle, and was being sued and/or blackmailed by former sex partners, depending on which tabloid was your source.

Asked this morning how many people he’d confided in since his diagnosis four years ago, Sheen quipped, “enough… to be in the position I’m in today.” The actor claims to be the victim of betrayal and extortion from people threatening to sell his secret to tabloids.

“I have paid those people. Not that many, but enough,” he said, when asked how many and how much. “I don’t want to guess wrong, but enough to bring it into the millions. What people forget: that’s money they’re taking from my children. I’ve got five kids and a granddaughter.”

Sheen insisted he “always led with condoms and truths” with sexual partners since his diagnosis. “My trust turned to their treason,” he added. Lauer wondered if he still was paying people for their silence. “Not after today I’m not….I release myself from prison today,” the actor declared.

It’s “impossible” that he transmitted HIV to any sexual partner, Sheen maintained, saying that since learning of his condition he’s had unprotected sex with just two people who “were under the care of my doctor and completely warned ahead of time.”

Asked if he’s told every one of his sexual partners since his diagnosis that he’s HIV positive, he responded, “Yes, I have. No exception.”

Making today’s announcement has given him relief “more than I thought possible,” Sheen said. He was joined by his doctor, Dr. Robert Huizenga, who declared Sheen “healthy,” not suffering from AIDS and that there is little chance, but not zero, he could transmit the disease through protected sex. But, Huizenga admitted he’s “petrified” lest his patient become depressed or begin to abuse drugs or alcohol and neglect to take his daily dose of medication. Sheen insisted he’s not doing drugs now, but is drinking  “a little bit.”

“A lot of people are saying you should stop drinking,” Lauer said, stating the obvious.”Perhaps the freedom of today will lead to that as well,” Sheen responded glibly.

Lauer asked Sheen to play Write the Headlines. “You can never predict how media’s going to roll with something,” Sheen said, declining the suggestion. “It would help if [the headlines] were a lot more forgiving and supportive than some of the garbage I was reading the last couple days. It can’t get much worse than that,” he said of headlines saying he has AIDS and is “intentionally spreading it.”

Sheen said his career is not over with this announcement, adding, “as we speak, the chairman of Sony is excited about doing [a] show again,” he said, adding, “There are a couple of films I could put start dates on.”

Sheen, 50, has made few public appearances since his FX comedy Anger Management wrapped nearly a year ago. The  star of Wall Street and Young Guns later migrated to TV and, as headliner of CBS’ hit comedy series Two And A Half Men, became one of the best-paid actors in TV, making about $1.3M per episode, until he was fired from the show in 2011 after a public showdown with creator Chuck Lorre and Warner Bros., during which Sheen insisted he was “winning.”