Army chief General Raheel Sharif signed on Monday black warrants for four militants involved in the Army Public School attack in December last year.The army chief signed the black warrants of Maulvi Abdus Salam, Hazrat Ali, Mujeebur Rehman and Sabeel alias Yahya nearly a year after the horrific massacre, Inter Services Public Relations (ISPR) said.This was the first such sentence endorsed by the army chief after an order of the Supreme Court on August 2015 which gave legal cover to the establishment of military courts.The move came after President Mamnoon Hussain rejected clemency appeals of the four convicts on receiving the premier’s advice for the same on November 20.Earlier, a military court sentenced all four terrorists to death after the government lifted the moratorium on the penalties in the country under the National Action Plan.On December 16 2014, militants launched an attack on the army-run school, killing over 150 people, mostly schoolchildren.