Inquiry call after drilling rig runs aground off Alaska
Senior members of the US Congress are demanding an inquiry after a Shell oil drilling ship ran aground off Alaska.
The Kulluk broke away from two tug boats during storms on Monday.
Salvage crews have been struggling to recover it because of high seas and strong winds.
Shell insists that no oil has been spilled but the incident has heightened concerns about the environmental risks of drilling in the Arctic.
The BBC's Steve Kingstone reports from Washington.
04 Jan 2013