BBC News with David Austin

The biggest city in northern Nigeria, Kano, has been hit by a series of bomb attacks. The regional police headquarters and police stations were among the targets. Gunfire was heard in several locations. Reports from Kano suggest at least six people have been killed. The BBC's Mark Doyle is in Kaduna in northern Nigeria.

What appears to have been a coordinated series of attacks against police stations has taken place in the last couple of hours. We've been speaking to residents in Kano. It's about three hours' drive from where I am now. Residents confirm and eyewitnesses confirm that at least six blasts took place, at least five of those at police stations. One of the police stations is reportedly very, very badly damaged. It may have been some sort of car bomb, and it may be many more police stations, but as (I say) residents say at least six.