 On 1 May 2011, in a clandestine operation in Abbottabad, al-Qaeda leader Osama Bin Laden was located and killed by the U.S. Navy SEALs in his private compound.The groups affiliated with the armed TTP vowed, via media, to avenge Osama's death upon the Pakistan Armed Forces.On 21 and 28 April, senior al-Qaeda operative Ilyas Kashmiri conducted a series of coordinated terrorist attacks on the Pakistan Navy presence in Northern and Southern contingents.