Nigerian city on edge after bombings that killed at least 156 "That's the scary part, not knowing," says Kano resident Authorities lift a curfew imposed in Kano after the attacks The number of deaths is expected to rise, a military official says Lagos, Nigeria (CNN) -- A northern Nigerian city targeted by bombs and a hail of gunfire remained on edge Sunday after blasts that killed at least 156 people and left the police headquarters and other government buildings in charred ruins. Authorities lifted a daytime curfew imposed in Kano, the nation's second-largest city, after the bombings that hit eight government sites Friday. But an overnight curfew remained between 7 p.m. to 6 a.m., according to residents Shell-shocked residents wandered the streets, looking for loved ones. Others hid behind barricaded doors, too scared to leave for fear of more attacks. "That's the scary part, not knowing," said Faruk Mohammed, 27, who lives near one of the bombed police stations. We don't know what's going to happen next, no one thought this would ever happen here. There's a general sense of despair. The attacks paired bomb blasts with shootings on various sites including police stations, the passport office, state security headquarters and the immigration office. "I counted at least 25 explosions ...," Mohammed said. Then it went deathly quiet. Kano is a bustling city ... I've lived here for years and it has never been quiet, even at night. But after the bombings stopped, the only noise you could hear were dogs barking. The number of deaths is expected to rise, according to a military official who did not want to be named because he is not authorized to talk to the media. "The hospitals are not equipped to deal with the influx and severity of the injuries, so we are expecting that figure to go up," the official said. About 50 people were injured and search-and-rescue operations are ongoing, according to Nwankpa Nwankpa, a Red Cross information officer in the capital, Abuja. Islamist group Boko Haram -- whose name means "western education is sacrilege" -- claimed responsibility for the blast in a phone call to the Daily Trust, according to journalists at the newspaper. The group has been blamed for months of widespread bloodshed, with churches and police stations among the targets. The man suspected of masterminding those attacks was briefly captured this week before escaping police custody while being transferred to another prison. Depending on the faction, Boko Haram's ambitions range from the stricter enforcement of Islamic Sharia law across the predominantly Muslim north of Nigeria, to the total destruction of the Nigerian state and its government. Its grievances remain local, but it has attacked international institutions --- such as the United Nations -- on Nigerian soil. An August 26 attack -- during which a Boko Haram suicide bomber drove a jeep laden with explosives into the U.N. headquarters in Abuja -- was one of the deadliest in U.N. history. The group was formed in 2002 by Islamic preacher Mohammad Yusuf as an outgrowth of ethnic tensions in the country in the 1990s. Nigeria's population is split between mostly Muslims living in the north and predominantly Christians in the south. Yusuf advocated the institution of Sharia law throughout the northern states and opposed democracy. The group operated openly out of northeastern Nigeria and staged small-scale attacks against government targets. In 2009, Nigerian police forces moved to crack down on Boko Haram. Harsh police tactics led to an armed uprising and the arrest of Yusuf, who later died in police custody. The death spurred the group to begin its attacks on police stations. Ensuing clashes between group members and the police killed hundreds. The following year, Boko Haram re-emerged as a more radicalized, insurgent style group, staging assassinations and attacks in the north against not only government targets, but also churches and even a beer garden. "We're dealing with a movement of inchoate rage," said John Campbell, a U.S. ambassador to Nigeria who left his post in 2007. "It's highly decentralized, but what it has in common is a strongly Islamic character, and hatred for the secular, political economy of Nigeria, particularly the federal and state governments," he said. CNN's Nima Elbagir and Faith Karimi contributed to this report.