Police were called to a main road in Leigh Park this morning after a gas explosion near a row a shops.
The power in parts of Park Parade had been out since about 8.45am.
The News understands that an electrician had been attempting to replace a fuse at a substation close to the Iceland store when the explosion happened, at about 10.30am.
The force of the blast shot a cast-iron manhole cover into the air, cracking it.
Stuart Hoepfner-King was doing some maintenance work nearby and was startled by the bang.
The 42-year-old, of Havant, said: ‘I was on the walkway when I heard the sound of an explosion.
‘The metal cover went right up in the air from the manhole. It broke the cast-iron plate.
‘The explosion shook the buildings and shook the shops. It was a serious boom.’
Friend Derek Powell, who owns the TimeOut Café in Park Parade, was nearby.
The 51-year-old said: ‘It was a proper bang. There was a smell of gas afterwards.’
Others feared that the incident had been a bomb detonating.
Café worker Chyna Crawford, 16, was in the Leigh Café behind the explosion site.
She said: ‘It was quite scary. The whole place shook. A lot of people out the front thought there was a bomb.’
Police rushed to the scene shortly after, accompanied by fire service personnel.
They sealed off all access to the car park behind Iceland while engineers sought to fix the fault.
In a message to businesses in the area, Scottish and Southern Electrical apologised for the problem and said they would have power restored by 7pm today.
However, some businesses say they have lost out on hundreds of pounds of trade because of the error.
The power outage has affected Iceland, the Sue Ryder charity shop, Savers and the Leigh café.
Halil Kestek, 45, is the owner of the Leigh Café. He said: ‘This is very frustrating. We have lost out on a day of business. We have lost about £400 to £500.’
SSE said it would update locals on the repair at 4pm.