An Antonov cargo plane operated by a Ukraine-based airline crashed on Saturday near the city of Kavala in northern Greece, authorities said. Greek Civil Aviation authorities say the flight was headed from Serbia to Jordan, but were unable to confirm how many people were on board or what the plane’s cargo was. It was operated by Meridian, a freight company. The pilot managed to alert the authorities of a problem with one of the plane’s engines and was given the option to land at either Thessaloniki airport or Kavala airport. He chose Kavala, which was closer, but the plane crashed about 40 kilometers west of the airport, Greece’s Civil Aviation Authority said. “We were hearing explosions until a few minutes ago,” Philippos Anastasiadis, mayor of the municipality of Pangaios, told The Associated Press. “I’m about 300 meters from the crash site.” Locals reported seeing a fireball and a plume of smoke. The explosions have sparked speculation among locals and some Greek media that the plane was carrying explosives. State broadcaster ERT reported that army explosives experts were heading to the site, which is located on farmland near two villages belonging to Pangaiou municipality. The fire department has cordoned off the area.