By Geoffrey Smith Investing.com -- U.K. natural gas prices spiked on Thursday after reports of an incident at a Norwegian gas processing facility linked to a field that meets up to 20% of the U.K.'s daily demand. Front-month Futures rose to as much as 330 pence a therm, a two-week high, before retracing to stand at 310p/th by 04:15 ET (08:15 GMT), after newswires reported Norwegian police as saying they had "clarified" the incident. Earlier reports had said that the processing facility at Nyhamna, which receives gas from the giant Ormen Lange field, had had to be fully evacuated, but hadn't specified why.