The three soldiers and two civilians died as President Joseph Kabila was returning to the capital, Kinshasa while another 11 people were injured.
A presidential spokesman confirmed the accident saying it was caused by “heavy rain”, although early reports suggested speed was a factor. Witnesses told Radio Okapi [in French] speed was “the main cause” of the incident, which happened 220km (110 miles) south of Kinshasa.
Communications official Yvon Ramazani told AFP “a vehicle in the presidential motorcade was hit on the Matadi highway at Kimpese by a truck carrying cement” on Tuesday evening. Mr Kabila, who had been opening an oil rig and administrative building in the port city of Matadi, “stayed on the site until the emergency services arrived, and personally supervised the ambulance evacuation of dead and injured”.