Nigerian troops recovered weapons in raids on suspected Boko Haram bases in two northern cities, officials said Saturday. A raid in Tudun Bayero, some 10 kilometers from Kano, northern Nigeria\'s largest city, was carried out early Saturday after a tip-off, Kano State director of State Security Service (SSS) Basil Etang told Agence France Presse. He said items recovered included 33 improvised explosive devices, nine rifles, 139 rounds of ammunition, ammonia fertilizer and nitric acid. \"We also discovered some military uniforms being used by the terrorist elements to commit their crimes\", he said, adding that three suspects were arrested. The raid in Kano came two days after another cache was discovered in Maiduguri, another hotbed of the Islamists, where four AK-47 assault rifles, a machine gun and ammunition was recovered, another security official said. Nigerian soldiers have stepped up their crackdown on members of Boko Haram which launched an uprising in 2009 which was brutally put down, leaving hundreds dead. The group has killed more than 1,400 people since 2010 in attacks across northern and central Nigeria, according to a new toll released this week by Human Rights Watch.