KANO, Nigeria (AP) — A woman blew herself up at a petrol station in northern Nigeria on Monday, killing three people in the second female suicide bombing in Kano in two days, police said. Female suicide bombers are rare in Nigeria but women seem to be playing an increasingly large role in the conflict after more than 200 teenage girls were kidnapped in April. The group says it wants to impose its harsh version of Islamic law on the region, but it often attacks mosques, sheiks and Muslim civilians.