The police said the incident took place Makindye Lukuli, on the outskirts of the country’s capital Kampala.
Local council Chairman, Twaha Bogere, said: “40 people have been working on the building but 20 of them spend nights at the site due to the COVID-19 curfew. It is those who sleep at the working place which have perished.”
Initial investigations have shown that the materials which were being used for the construction of the four-story building were substandard.
A Kampala city council engineer, Douglas Nsubuga, revealed that they had earlier instructed the owners of the edifice to stop work since they were not following the required standards.
However, the owners did not listen to the instructions from the city authorities.
Mr Nsubuga added that the chief engineer at the site had reportedly not been there for some time leaving his inexperienced assistant to act in his stead.