YOLA, Nigeria – Suspected insurgents armed with guns and explosives killed at least 62 people in northeast Nigeria, including at a church service, in a region where Islamist sect Boko Haram is resisting a military crackdown, witnesses said on Monday. They killed 22 people by setting off bombs and firing into the congregation in the Catholic church in Waga Chakawa village in Adamawa state on Sunday, before burning houses and taking residents hostage during a four-hour siege, witnesses said. On Monday, a separate assault by suspected members of the shady sect killed at least 40 people in Kawuri village, in remote northeastern Borno state, security officials said. No one immediately claimed responsibility for either attack. President Goodluck Jonathan is struggling to contain Boko Haram in remote rural regions in the country's northeast corner, where the sect launched an uprising in 2009. Boko Haram, which wants to impose sharia law on a country split roughly equally between Christians and Muslims, has killed thousands over the past four and a half years and is considered the biggest security risk in Africa's top oil exporter and second largest economy after South Africa.