The Prime Minister of Pakistan, Nawaz Sharif, has led the condemnation of the killing of leading human rights activist Sabeen Mehmud. Sabeen Mehmud was shot dead in Karachi as she drove home with her mother, who was injured in the attack. A statement from Mr Sharif’s office expressed condolences and ordered an immediate investigation. No group has yet said it carried out the killing; the campaigner been subject to death threats before.