Four Pakistani nationals working for an international NGO have been abducted by an unidentified group in Balochistan, report said on Friday. The four workers of Mercy Corps, a relief organization working in the province since last 15 years, were going from Zhob to Quetta when their vehicle was stopped near Shinkai Shamozai area in Qilla Saifullah and they were taken away by some unidentified persons, local officials said. Balochistan Home Secretary Akbar Durrani said a search was launched for the NGO workers after police learnt about their abduction on Friday. He said all the four were Pakistani nationals. Durrani said a witness had seen the car in which the NGO workers were travelling being stopped in Qilla Saifullah.