The Kenya Red Cross on its twitter says the accident occurred at 5:45am.
Police had difficult time directing traffic that had started building up in the area.
Drivers have been urged to exercise caution especially when approaching Limuru, Nairobi-Nakuru Highway due to the thick fog.
“In less than 24hours two accidents have claimed 17 lives. #Roadsafety begins with me. Be mindful of others on the road. #StaySafe,” Kenya Red Cross posted on its twitter account.
“Thick fog at Limuru, Nairobi-Nakuru Highway… Drivers please drive with caution.”
11 people also died on spot when their Nairobi-bound matatu collided with a trailer at Quarry on the Nakuru- Eldoret highway. Only one of the passengers survived.