Kenyan highway authority said Monday it has closed down a section of a busy highway to western region and neighboring countries after Sunday evening's earth tremor caused a fault line on a bridge along the section.

The Kenya National Highways Authority (KeNHA) advised motorists to avoid the Mai Mahiu-Naivasha road amid fears that the bridge could collapse.

The highway authority called on heavy commercial vehicle operators to exercise caution and restraint, and to follow traffic flow directions that are being provided by the traffic police.

"Particularly, we advise all motorists to observe lane discipline and avoid overlapping, which can result in traffic flow disruptions," KeNHA said in a statement.

KeNHA said its engineers are on site monitoring any resultant damages to the road surface.

Disruption of the traffic flow was expected to impact on business in western Kenya as many trucks use the highway ferrying transit goods to Uganda, Democratic Republic of Congo, Rwanda, and other parts of western Kenya.

A light earthquake of magnitude 4.8 on the Richter scale was experienced in southeastern Kenya on Sunday evening, Kenya Meteorological Department said on Monday.