Pakistani police warned the military in July that the audacious raid on their headquarters was being planned, intelligence officials said Sunday. The mastermind of the attack also planned two other major attacks in the past two years, including the attack on the Sri Lankan cricket team in Lahore earlier this year. Nine men wearing army uniforms held dozens hostage for 20 hours until a raid ended the siege on Saturday. Eight of the attackers were killed, leaving only Muhammad Aqeel, who officials say is the mastermind of the attack. The criminal investigation department of the police wrote a letter warning that the military’s headquarters would be attacked. The letter was reprinted in the leading newspaper on October 5. The fact that the military was warned further calls into question their ability to fight off militants and keep their nuclear arsenal safe from the Taliban, The New York Times reports, though Hillary Clinton brushed aside the question of the nukes’ safety on Sunday. One of the attackers wore a suicide bomb jacket, but was killed in the siege before he could detonate himself. Another suicide bomber did blow himself up, bringing down the roof and injuring some captives. In all, 16 people were killed.