Emergency services are battling to subdue a huge gas plume 'roaring' out of the ground in Blackbird Road, Leicester.
A main in the street has ruptured and gas can be seen pouring out of the pipe in a plume towering over workers in the area.
Roads around the area have been blocked off by emergency services due to the leak, which can be heard at least half a mile away.
Eyewitness Andrew Wells was eating a family meal in the nearby Blackbird pub when the leak occurred.
He said: “The gas main must have a very high pressure leak by the sound is was making, a very very loud rushing sound.
“I’m at home .4 or .5 miles away and I can still hear it.
“We were told at first to move to the back of the restaurant, away from the front windows.
“I said can I move my car as it was parked in the car park near the main road, and when I went outside and heard it I went back inside and said we were leaving, and suggested they should evacuate.
“I gather that’s what they’ve done now.”
Dean Poyser has said on Twitter that he can hear the gas ‘roaring out’ of the main. He adds: “Nobody light a fag!”
While Paul Bayliss said: “It’s pandemonium. Avoid like the plague.” Leicestershire Police are diverting traffic.
A spokesman said: "Police incident at the junction Blackbird Road/Anstey Lane.
"This has resulted in roads around here being close and traffic is building up please find alternative routes.
"There is no access from Parker Drive including side roads through to A50 and from Buckminster Road on Anstey Lane."
Area Traffic Control Leicester say the A50 Groby Road and Woodgate are both struggling as a result.
They add: “Avoid the area if you can.”