Fire crews in Londonderry have tackled a huge blaze at a retail park in the city.
It started in a carpet store at Crescent Link at about 0430 GMT on Sunday.
The blaze caused extensive damage to the end row property, occupied by Carpet Right.
The scene was examined by forensic scientists to establish if it was arson.
However, a preliminary investigation into the fire has proved inconclusive.
Up to 40 firefighters tackled the blaze.
Divisional fire officer Gerry Warren said firefighters managed to prevent flames setting fire to other business premises.
"The roof collapsed inwardly on the building," he said.
"The firefighters did a wonderful job in stopping the fire spreading to the adjoining units.
"The building itself is a bit unsafe at the moment and we have to put in some safety measures before we can get inside and establish the exact cause of the fire."
The police are investigating the cause of the fire.
Damage caused to stock at the carpet store is reported to exceed £100,000.