A gas blast alarmed residents in Motherwell’s Airbles Road yesterday.
It happened after repairs had been carried out to a pipe under the road.
One resident said the explosion blew a manhole cover 10 feet into the air.
No one was injured and gas distribution network company SGN said that while the cause is being investigated tests have shown no leak of gas in the vicinity.
Airbles Road had been closed since Thursday for the emergency repairs, causing diversions for drivers.
A resident said workmen had excavated in various spots and completed their work on Saturday.
The explosion happened on Sunday morning as a road resurfacing crew were tarring over the excavated areas.
The resident said: “The explosion would suggest there is gas underground still and that a leak has not been plugged.
“This is of great concern on a main road artery and close to residential flats.”
SGN confirmed an incident had taken place, but insisted there is no cause for alarm.
Spokesman Katie Lobban said: “Our engineers started emergency repair work to our gas main in Airbles Road on Thursday. To enable us to carry out the work safely, a road closure was in place.
“Our permanent repair was completed by Saturday morning and work then began to reinstate the road surface.
“As this work was being carried out yesterday a nearby manhole cover was lifted off. The cause is under investigation.
“Safety checks were carried out and there were no gas readings in the vicinity or in the sewer.”