A report released by Shahid Nadeem Baloch, the police chief of Sindh province, said the explosive materials were seized between September 5 and December 6.
Police launched a special crackdown on criminals and terrorists in Karachi, which has witnessed law and order problems and hundreds of killings in recent years.
The report said 9,944 alleged criminals were arrested, including 102 terrorists, 269 wanted criminals, 3,056 fugitives, 40 kidnappers and 61 extortionists.
Various amounts of arms and ammunition were recovered by police.
The number of raids conducted during the period is 4,849, with 546 shootouts in which 89 dacoits were killed.
Two suicide vests, five rocket launchers, 156 rockets, 2,445 pistols, 84 shotguns, 56 rifles, 70 Kalashnikovs, three LMGs, and 17 kg of heroin were seized during the drive.