A plane has crashed in the north of South Sudan killing at least 20 people, Unity state minister for information said Wednesday. The aircraft came down near the oil fields in Unity State at around 10:30 am local time (0830 GMT) shortly after taking off for the capital Juba. “The plane crashed 500 metres away from the airport. 21 people were on board. As for now, there’s only one survivor,” Gatwech Bipal Both told AFP by phone. He said the aircraft, chartered by the Greater Pioneer Operating Company (GPOC) and operated by Light Air Services Aviation Company, was on a…