Traffic has been disrupted along Thika Road at Ndarugo near the entrance to Mang'u High School and the entrance to the highway at Witeithie.
In videos seen by Kenyans.co.ke, the bonfires have been lit at several spots across the highway, affecting motorists from both sides.
Videos show vehicles traversing through the busy highway, weaving through the bonfires as they quickly rush through the burning tyres to avoid contact with the smoky, flaming fires.
The motivations for the protests are still unclear, though reports suggest they were sparked by the alleged abduction and torture of Juja MP George Koimburi.
Meanwhile, those responsible for the fires have not been identified, as they were absent from the scene. Additionally, the motives behind the arson remain undisclosed at this time.
The fires broke out just moments after former Deputy President Rigathi Gachagua visited the area's Member of Parliament at the Karen Hospital, where he is being treated for injuries he sustained while in captivity.
Although unverified, social media reports from passersby allege that the fires were in solidarity with their hospitalised lawmaker.
After evading abduction on Saturday and going into hiding, Koimburi resurfaced at a church service on Sunday, after which he was forcefully abducted by unidentified persons.
While confirming the incident to Kenyans.co.ke, Kiambu Senator Karung'o Thang'wa, a fellow Gachagua ally, revealed that Koimburi's wife had been injured during the altercation.
On Monday morning, the lawmaker was found dumped at Jacaranda Coffee Plantation in the Kibichoi area of Ruirua coffee farm in Kiambu County after 18 hours in captivity.
He was found in a dire state and unable to speak, and was immediately rushed to a nearby hospital before his transfer to the Karen Hospital for specialised treatment.
After visiting the MP at the hospital, Gachagua claimed that the MP was poisoned with a chemical that paralysed his vocal cords, impeding his speech.
“I have seen him and talked to the doctors. They have confirmed that George Koimburi was tortured by professionals. He has soft tissue injuries, a kind of torture done by professionals. He has lost his voice, and the doctors are working around the clock to restore his vocal cords," Gachagua said.
"We have been told by doctors that some chemicals were administered through inhalation, but he is out of danger."
