The death toll from a fireball caused by a crash involving a tanker carrying flammable materials rose to 40 Monday, as Kenya faced calls to improve safety on its perilous roads.

The east African nation was left reeling by devastating scenes from the crash late Saturday in which the tanker ploughed into 11 vehicles, leaving a trail of incinerated wreckage and bodies along the main road leading west from Nairobi towards Uganda.

And one of the injured succumbed to their wounds in hospital.