Experts were set to search the plane’s crash site in northern Greece on Sunday to determine if there were dangerous chemicals or an explosive charge. The An-12 cargo plane crashed in fields between two villages late Saturday. Local residents reported seeing a fireball and hearing explosions for two hours after the crash. A plume of white smoke was still rising from the front of the plane Sunday morning. Serbian Defense Minister Nebojsa Stefanovic told a news conference on Sunday that all eight crew members were killed. He said the plane was carrying 11.5 tons of Serbian-made mortar ammunition to Bangladesh, which was the buyer. It had taken off from the Serbian city of Nis and was due to make a stopover in Amman, Jordan. The plane was operated by the Ukrainian cargo company Meridian, and the Ukrainian consul in Thessaloniki, who arrived at the crash site, told local officials that the crew was all Ukrainian. “These were mortar mines and training (mines). … This flight had all the necessary permits according to international regulations,” Stefanovic said. The aircraft crashed shortly before 11 p.m., about 40 kilometers (25 miles) west of Kavala International Airport. Minutes earlier, the plane’s pilot had told air traffic controllers that there was a problem with one of his engines and that he had to make an emergency landing. He headed to Kavala airport but never got there. The plane is a Soviet-era four-engine turboprop cargo carrier. Drone footage shows that small pieces of debris are all that is left of the plane. Firefighters who rushed to the scene overnight were unable to reach the crash site due to smoke and a strong odor they feared might be toxic. Residents of the area were asked to keep their windows closed throughout the night, not to leave their homes and wear masks. Authorities said they did not know if there were any hazardous chemicals on the plane, including those contained in batteries. A special army unit looking for nuclear, biological and chemical agents will comb the site but is not expected to arrive before 13:00 (10:00 GMT). The fire department has cordoned off the area in a radius of about 400 meters. The mayor of the municipality of Pangaios, to which the two villages near the traffic accident belong, prohibited the movement of vehicles on nearby roads. —— Nellas reported from Athens, Greece and Gec from Belgrade, Serbia.