International medical charity, Medecins Sans Frontieres (MSF), has condemned the killing of one of its nurses in Zamfara state, north-west Nigeria.
The nurse, Hassan Muhammad, was returning to his work station on Saturday when gunmen opened fire on the public vehicle he was travelling in.
Local media report that two other people, the driver of the vehicle and a passenger, were also killed in the attack.
The charity said it was shocked and saddened by the death of the 37-year-old nurse who worked in Shinkafi town, where its team runs a facility at the local hospital.
Shinkafi is one of the areas most affected by attacks in Zamfara State.
The state has seen a surge in violence where gangs seeking ransom have carried out mass abductions of students from schools and attacked villages and people travelling by road.
The authorities recently shut down phone communications in the state to enable security forces to fight the gangs.