The falling rocks are due to the recent heavy downpour experienced in the area.
The disruption has left hundreds of travelers stranded, highlighting the critical need for immediate repairs to restore connectivity.
KeNHA cautioned that the river is nearing overflow, posing a danger to road users.
The auuthority said the sudden siltation occured at Suswa area, about 27 kilometres from Mai Mahiu town towards Narok.
The most affected areas were Tula and Arer, a few kilometres to Bangale town.
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