The manhole flew up in the air on Tuesday at about 08:00 BST
A woman and two children had a "lucky escape" when a manhole exploded behind them as they used a cash machine.
CCTV footage shows the trio fleeing the blast, as the manhole cover and lumps of pavement are thrown up in the air outside shops on Wellingborough Road, Northampton.
East Midlands Ambulance Service said three people sustained minor injuries.
Northamptonshire Fire Service said the cause appeared to be an electrical fault in a network junction box.
Abington Supermarket's sign was damaged, while work continued to fix cabling under the pavement
Debris from the blast, outside Abington Supermarket, damaged the sign above the shop's windows.
'Running and screaming'
Laura Abbott, who works at the neighbouring Gilders country clothing shop, said the manhole was "about a metre" from the cash machine.
"These people had a lucky escape as someone could easily have been seriously injured," she said.
"I heard the explosion and it shook our building.
"It looked like the manhole cover and concrete went at least 2m (6ft) up in the air."
An ambulance service spokeswoman said: "The caller [to the emergency services] claimed to hear a large bang followed by lots of people running and screaming."
The three injured people were treated at the scene, she added.
Northamptonshire Police closed a section of the road after the explosion, which happened at about 08:00 BST on Tuesday.
The road has since re-opened, but Western Power is carrying out repairs to underground cabling.
The firm said its investigations were ongoing.
- Published4 June 2015
