Twelve homes were evacuated after a ruptured gas pipe ignited.
The drama happened in Willow Road, Hunstanton, just before 4pm.
Police and firefighters sealed off the street, while gas engineers made the scene safe.
Station manager Bob Ayres said the leak occurred after a member of the public cut through a gas pipe.
'Someone was using an angle grinder to cut through concrete,' he said. 'Sparks from the grinder ignited the gas. There was a metre-high flame.'
Mr Ayres said the flame went out, leaving a cloud of unignited gas in the property and 12 neighbouring homes were evacuated as a precaution.
Firefighters from Hunstanton, Heacham and King's Lynn used a water jet to cool the area around the leak. Mr Ayres said fire crews would remain on the scene until the supply was made safe.
Police duty inspector Chris Tomkinson said: 'We assisted with the diversions but I am not aware of any criminal matters.
'Twelve households were advised not to go in their front gardens.'
Cllr Amanda Bosworth, mayor of Hunstanton said: 'I'm shocked by it. I shall be trying to find out what's happening and why.
'Obviously my thoughts go to the people who are evacuated.
'I have to say it really reinforces the need for our fire services. Once again they have come to the rescue this summer.
'Between them and the coast guard rescuing people on the sand banks it really brings home how important having services nearby is, particularly with a rural town like us.'
Norfolk Fire and Rescue Service handed the site over to the gas board at 7.15pm.
Anyone who smells gas should call the National Grid gas emergency line on 0800 111 999 as soon as possible.
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