In the latest in a number of similar tragic incidents over the past few years, at least five people have died and dozens more were injured after the roof of a five-story cement factory collapsed in South Bangladesh on Thursday.

At least 40 people were reportedly rescued from the debris after the building collapsed in the Mongla Port Industrial Area, while some 100 more remain trapped, Reuters reported.

"Most of the people inside the building were the construction workers including the people who recovered alive ... The recovery efforts are going on very carefully to avoid further risk," Khulna district police chief Nizamul Haque Mollah said.

An estimated 150 people were working in the factory at the time of the collapse, according to Belayet Hossain, an officer in charge of the Mongla Port police station close to the factory.

The Mongla Cement Factory was still under-construction during the collapse. While the army owns the factory compound, a Chinese-owned company was behind the construction.