Three partly-built houses were destroyed after fire ripped through a construction site in Motherwell on Monday night.
Three crews of firefighters tackled the blaze, ironically at a development in Vesuvius Drive, near Craigneuk Street.
Neighbours reported hearing an explosion before smoke began billowing into the air.
A Scottish Fire and Rescue Service spokesman said the first firefighters arrived at the scene within five minutes of being alerted around 11.15pm. Two crews from Motherwell were joined by one from Coatbridge.
The spokesman said: “Our crews were confronted with an intense fire within six two-storey buildings that were still under construction.
“Three properties were destroyed by the fire and only the determined efforts of the crews prevented all six buildings being lost.”
After putting out the flames the firefighters remained to conduct dampening down operations, with a thermal imaging camera used to confirm there was no hidden fire spread.
The spokesman added they are now working with the police to establish the circumstances surrounding the fire.