The four died after being buried alive by a trench that collapsed on them while doing construction works.
Jawadi Investments, a local company was contracted by North Western Water and Sewerage Company to do construction works.
Rescue efforts continue to retrieve the remaining bodies.
Solwezi District Commissioner Rosemary Kamalonga who rushed to the scene has confirmed the sad development.
Kamalonga said it was devastating to lose such a number of people while on duty to earn a living.
She has described the incident as an unfortunate and very sad and could however not give further details.
Provincial Commissioner of Police Hudson Namachila said he would give details at a later stage.
Meanwhile, residents of Solwezi trooped to Solwezi Hospital Mortuary to identify the bodies of the deceased.