(CNN) -- Los Angeles Lakers forward Metta World Peace has been suspended for seven games without pay over an elbow blow he delivered to the head of an opposing player, the National Basketball Association said Tuesday. One-time basketball bad boy Ron Artest, who changed his name to Metta World Peace, was ejected Sunday from a Los Angeles Lakers-Oklahoma City Thunder game for striking James Harden. "The concussion suffered by James Harden demonstrates the danger posed by violent acts of this kind, particularly when they are directed at the head area," said NBA Commissioner David Stern, to announce the suspension. "We remain committed to taking necessary measures to protect the safety of NBA players, including the imposition of appropriate penalties for players with a history of on-court altercations."
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NEW: Metta World Peace apologizes to Oklahoma City Thunder fans
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He is suspended without pay for elbowing Thunder's James Harden
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World Peace could miss at least six playoff games, the NBA says
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Lakers GM: "His most recent lapse ... is not to be condoned or accepted"
Oklahoma City Thunder
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He apologized Tuesday to @placeholder fans and the Oklahoma organization.
Oklahoma City Thunder
Oklahoma City Thunder
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He apologized Tuesday to Thunder fans and the @placeholder organization.
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"I look forward to getting back on the floor with my teammates and competing for the @placeholder fans," he said.
Oklahoma City Thunder
Oklahoma City Thunder
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After scoring against the @placeholder in the second quarter, World Peace was cheering his own shot when he hit the Oklahoma City guard in the back of the head, knocking him down.
Oklahoma City Thunder
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After scoring against the Thunder in the second quarter, World Peace was cheering his own shot when he hit the @placeholder guard in the back of the head, knocking him down.
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The @placeholder won 114-106 over the Thunder in double overtime.
James Harden
James Harden
James Harden
It was unfortunate that @placeholder had to get hit with an unintentional elbow," World Peace told reporters after the game.
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Los Angeles Lakers
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"Metta has for the most part been a model citizen both on and off the court since joining the @placeholder.
National Basketball Association
NBA
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For that incident, the @placeholder suspended Artest for 86 games.