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ADEN, March 2 (Reuters) - A Yemeni Islamist group linked to al Qaeda said on Friday it had attacked and killed a CIA officer in the southern province of Aden, but a Yemeni security official and the Pentagon said a U.S. security team had been attacked but suffered no injuries.
In a text message sent to journalists in Yemen, Ansar al-Sharia said: "The mujihadeen (holy warriors) killed a CIA officer on Thursday while he was in Aden province, after tracking him and determining he was cooperating with the Sanaa government."
The claim follows a suicide attack last month in another southern city that the group said it carried out against a Yemeni military unit which Washington has funded and armed to fight the country's al Qaeda wing.
A Yemeni security official in Aden said a gunman fired on a U.S. security team involved in training Yemeni security forces on Thursday, but the shots had hit their armoured vehicle without injuring anyone.
In Washington, a Pentagon spokesman confirmed that a gunman fired several shots at an armoured vehicle carrying a U.S. security team in Yemen and that no one was injured.
Fears that political turmoil in Yemen would empower al Qaeda led Washington and Saudi Arabia to broker the replacement of Yemeni President Ali Abdullah Saleh with his deputy last month, after a year of mass protests against him and fighting between factions of the Yemeni military allied and opposed to Saleh.
The suicide attack last month, which killed 26 people in the city of Mukalla, came hours after the new president, Abd-Rabbu Mansour Hadi, was sworn in and vowed to fight al Qaeda.
Islamist militants have taken control of swathes of territory in southern Yemen during the struggle over Saleh's fate, and control the city of Zinjibar in southern Abyan province, where ensuing fighting with government forces has led much of the population to flee.
Opponents of Saleh - once a key to U.S. "counter-terrorism" policy - accuse him of ceding ground to militant Islamists to bolster the claim that he alone could hold al Qaeda in check, and maintain his grip on power as pressure to oust him rose. (Reporting by Mohammed Mukhashaf; Writing by Joseph Logan; editing by Tim Pearce)