Three policemen have been killed in the Hangu area of north-west Pakistan when their patrol vehicle came under attack from suspected militants, officials say.

Local media reports say that the unit was on a routine patrol when it was ambushed by unidentified gunmen.

Security forces have cordoned off the area, reports say.

Hangu, in Khyber-Pakhtunkhwa province, has a history of attacks by militants who frequently target security forces

The area also has a history of violence between its Shia and Sunni communities.