76 Tung Ming Street in Kwun Tong, Kowloon. Photo: Google Maps.

A 61-year-old Hong Kong security guard, who also did part-time work as a decorating contractor, was found dead on a staircase next to a bag of cement in Kwun Tong in Kowloon on Tuesday.

The man surnamed Cheung was found unconscious at 8am on the stairs by the eighth floor of a tenement house at 76 Tung Ming Street in Kwun Tong. He was certified dead by paramedics at the site.

A bag of cement, that weighed about 40kg, was found alongside the man.

Apple Daily reported that Cheung, who had previously been diagnosed with colorectal cancer, was helping out a friend, working recently as a part-time handyman on a project to renovate a flat on the ninth floor.

Cheung worked overnight as a guard and finished work at 7am on Tuesday before rushing to Kwun Tong for the project.

After inquiries, police suggested that Cheung had collapsed due to being physically exhausted after carrying the bag of cement all the way up to the eighth floor, Sing Tao Daily reported.

A post mortem examination will be conducted later to determine his cause of death.