The Kapandu hall of residence was ablaze on Thursday morning despite the lack of an electric current.
The building was condemned following the 2016 student unrest.
A team from the Gerehu Fire Station responded immediately and put out the blaze while their superintendent, John Gareresi, ruled out electricity as it was disconnected years ago.
He said their investigation division will look into the matter, adding they were fortunate it was not windy on the day or the situation might have escalated.
UPNG vice-chancellor, Professor Frank Griffin, was also keen on an investigation, saying the cause of the blaze will be identified and addressed.
(Article and picture by Albert Moses – final year UPNG Journalism student)