At least 30 people were killed when a fuel tanker exploded in Port Harcourt, the hub of Nigeria's multi-billion-dollar oil industry, police and residents said."The incident happened at Eleme junction in the city. Details about the sad incidence are still sketchy," Rivers state police spokesperson Ireju Barasua indicated.It is however known from reliable sources that no fewer than 30 people burned to death when the petroleum-carrying tanker exploded and burst into flames.