(Adds fire department comment)
The oil major denied reports from trading sources that the plant was hit by a fire. The company said the units affected by the power outage were being restarted.
The Rotterdam fire deptartment said it had received no reports of a fire at BP's refinery.
Industry intelligence group Genscape reported that a 200,000 bpd crude distillation unit at the refinery was shut down this morning and elevated flaring had taken place, which is usually a sign of unit malfunction. (Reporting by Lin Noueihed, David Sheppard and Ron Bousso, editing by Louise Heaves and David Evans)