Boko Haram seizes Chibok, home of kidnapped schoolgirls Maiduguri, Nigeria - Islamic extremists in Nigeria have seized Chibok, forcing thousands of people to flee the town where insurgents kidnapped nearly 300 schoolgirls in April, a local official said Friday. The Boko Haram insurgents entered the town Thursday, shooting from pickup trucks and motorcycles, Bana Lawan, chairman of the Chibok local government, told The Associated Press. "Nobody can tell you what is happening there today because everybody is just trying to escape with their lives," he said. In Washington, State Department spokeswoman Jen Psaki said the U.S. is closely monitoring the situation in Chibok. We condemn these attacks in Chibok, a community that has already suffered too much. ... We remain committed to helping the government of Nigeria address the threat posed by extremist organizations, Psaki told reporters. In a separate development, a bomb exploded Friday night in northern Kano city, the second largest population center in Nigeria, killing six people including three police officers, according to the police. Resident Aliyu Yusuf Hotoro said many buildings shook from the force of the explosion from a car bomb in a gas station on a main road leading to Maiduguri, the capital of Borno state. Soldiers, police and emergency rescue operations workers cordoned off the area. There was no immediate claim of responsibility for the bomb, but Boko Haram extremists have detonated them in Kano in the past. Meanwhile, attempts to call the cellphones of some of the kidnapped girls' parents living in Chibok failed. Boko Haram extremists often destroy cellphone towers, and the military often cuts communications to areas under attack. Dozens of the kidnapped girls escaped in the first couple of days after their capture from a boarding school just outside the town, but 219 are still missing. Community leader Hussain Monguno said none of the escapees was in Chibok at the time of the attack. They have all been given scholarships to other schools in northern Nigeria. Nigeria's military chief announced on Oct. 17 that the country's homegrown Boko Haram extremist group had agreed to an immediate cease-fire. Government officials said the truce would lead to the girls' speedy release. But Boko Haram leader Abubakar Shekau in a video released last month said the girls were "an old story," that they all had converted to Islam and been married off to his fighters. Chibok is an enclave of mainly Christian families, some involved in translating the Bible into local languages, in the mainly Muslim north of Nigeria. At least seven of the girls' parents have died since their abductions, from causes such as heart attacks that residents blame on the trauma, according to Monguno, head of the Borno-Yobe People's Forum. Since the apparent cease-fire announcement, the insurgents have taken control of several more towns and villages where they have declared an Islamic caliphate along the lines of the Islamic State group in Iraq and Syria. In an area covering about 20,000 square kilometers (7,700 square miles), residents caught behind the militants' lines say they have set up courts upholding a strict version of Shariah law, publicly amputating the hands of alleged looters and whipping people for infractions such as smoking cigarettes. Associated Press writers Ibrahim Garba in Kano, Nigeria, and Matthew Lee in Washington contributed to this report.