UPDATE 1-Shell restarts Nigeria's Bonga offshore production

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LAGOS, June 24 (Reuters) - Royal Dutch Shell (RDSa.L) said it had restarted production at its Bonga offshore oilfield in Nigeria on Tuesday after an attack by militants last week.

"We have restarted production," said Precious Okolobo, a Shell spokesman in Nigeria. He declined to say whether the production had resumed at full capacity.

Militants in speedboats attacked Bonga, which has a nameplate capacity of 220,000 barrels per day (bpd) and lies some 120 km (75 miles) off Nigeria's coast, last Thursday, forcing the Anglo-Dutch giant to stop production.

Shell declared force majeure on Bonga shipments for June and July the next day, freeing itself from contractual obligations. (Reporting by Nick Tattersall; editing by James Jukwey)