The DCI officers sealed off NTSA headquarters, asking members of the public to come back later after they were done with their investigations.
According to reports, the detectives were in the premise to conduct investigations following the Dusit D2 terror attack.
This is after it was revealed that the car used by the attackers to access the Dusit D2 complex had similar number plates with another vehicle.
The second vehicle, also a Toyota Ractis, was impounded by police in Kitengela, Kajiado County, a day after the attack.
While impounding the car, Kajiado county police commander, Kipkemoi Rop, confirmed that they would hold the vehicle till DCI concluded its investigations.
The officers now want to unearth the NTSA officials who could have been involved in the registration mix-up.
Investigations to identify the culprits behind the Dusit Terror Attack has been intense with over 17 suspects arraigned in court.
The number of cases about vehicles with similar registration numbers and details has been on the rise recently, with fingers being pointed at the NTSA for the mistake.
This has led to speculations that some officials from the NTSA were colluding to process fake details for stolen vehicles.