ISLAMABAD- Strict security measures had been taken in Islamabad today following the airstrikes against militants in the North Waziristan tribal agency. Security sources said that Islamabad had been put on high security alert, adding that special measures had been taken at key buildings including President House, Prime Minister House and the Parliament. An exercise was also undertaken to scrutinize the staff of the Parliament House for which all the data was obtained, sources said. These security measures were taken to avert and deal with any criminal activity in possible retaliation by the militants. Pakistan Air Force jets pounded hideouts of militants in North Waziristan, killing over 30 terrorists.