The Directorate of Revenue Intelligence (DRI) has arrested two Zimbabweans with 7.9 kg of heroin worth Rs 50 crore at Chhatrapati Shivaji Maharaj International Airport here, an official said on Sunday. Based on specific information, the DRI's Mumbai zonal unit laid a trap at the airport on Friday and intercepted a man and a woman travelling from Addis Ababa (Ethiopia), the official said.