A policeman was killed and two US troops injured Monday in an apparent insider attack in eastern Afghanistan, officials said, according to dpa. "The incident took place at 12 pm (0730 GMT) in the Gardez police department when an American military adviser was meeting the provincial police chief," said Rohullah Samoon, governor's spokesman for Paktia province. "The motive of the attack is not clear yet," he said. A police source in Gardez said police opened fire on the bodyguards of the adviser waiting outside the police chief office. "The policeman injured them and was shot dead by the US troops," the source said. The NATO-led international military confirmed the incident.