NEW : The official declined to identify the units or their locations because of the sensitive nature of the information . The State Department says deployment of personnel is in response to a specific threat . Security steps increase in Yemen due to intercepted al Qaeda message , other threats . A pair of suspected US drone strikes kills two al Qaeda militants . ` ` Do something , '' reads a message from al Qaeda 's leader to his Yemeni deputy .
NEW : The State Department says deployment of personnel is in response to a specific threat . Security steps increase in Yemen due to intercepted al Qaeda message , other threats . A pair of suspected US drone strikes kills two al Qaeda militants . ` ` Do something , '' reads a message from al Qaeda 's leader to his Yemeni deputy .