Witnesses say militants from the Nigerian Islamist group Boko Haram have directly attacked the northeastern city of Gombe. The city has previously been the target of several bombings, but never an attempt at invasion.
Hundreds of Boko Haram militants attacked the northeastern Nigerian city of Gombe on Saturday, overrunning a checkpoint and firing heavy guns, witnesses and a security source said.
One witness said the militants had burned down a police station at the edge of the town, while others told AFP news agency the militants had distributed pamphlets calling on residents to boycott fortcoming elections.
Nigeria has postponed a presidential election, which had originally been scheduled for Saturday, by six weeks, citing the security threat posed by Boko Haram in the northeast of the country, where the Islamist group is carrying out a violent campaign to establish an Islamic state.
During the six-year insurgency, Gombe has been targeted by suicide attacks and other bombings blamed on Boko Haram, but has never been hit by a direct assault.
Two weeks ago, many people were injured in the city when two suicide bombers blew themselves up outside a stadium just minutes after President Goodluck Jonathan had given a campaign speech there.
The neighboring countries of Cameroon, Chad and Niger have joined Nigeria in battling the insurgents, who pose a regional threat with several cross-border attacks.
On Friday, Boko Haram attacked a village in Chad, the first know lethal assault by the group in that country. Residents and security forces said several people were killed, including a local chief.