The June 16 Islamic militant bombing attack was the first in Nigeria using suicide bombers. Boko Haram, the most active Islamic militants in the north, have, despite intense police pressure, promised more bombing attacks. The police say they will crush Boko Haram, but the Islamic radicals have been active for two years and have expanded the number and intensity of their attacks. Boko Haram is willing to negotiate a peace deal with the government, but only if Sharia (Islamic) law is strictly enforced in 12 northern states (out of 36 in Nigeria). This demand has been causing religious tensions in the north for most of the last decade.