KANO, Nigeria - Eight suspected Islamists were arrested in northern Nigeria on Thursday after police said they threw an improvised bomb at a police patrol vehicle but missed.

The suspects, believed to be from the Islamist sect Boko Haram, followed the police vehicle in a taxi In the city of Kano before hurling explosives out of the window, but missed their target, police spokesman Magaji Musa Majiya said in a statement.

"The police officers swiftly disembarked, cordoned off the area and arrested the eight occupants," he said. "No injury was sustained during the attack."

Boko Haram has become the main security threat to Africa's top oil producer.

At least 2,800 people have died in fighting in the largely Muslim north since the sect launched an uprising against the government in 2009 in a bid to impose Sharia law on Nigeria, watchdog group Human Rights Watch says.

Its fighters usually target security forces, politicians or Christians worshippers.

Kano, Nigeria's second biggest city, has been relatively quiet in the latter half of this year. In January, it was scene of the single deadliest attack of the insurgency, a coordinated strike on several police stations in which 186 people were killed, many of them civilians.