The Cooperative department of Embu county has warned matatu owners against operating under unregistered saccos.
Official David Muriuki said the vehicles will be impounded.
Addressing the owners in Embu town on Thursday, he gave them until August 1 to ensure they are under registered saccos.
The National Transport and Safety Authority has complained about the operators.
Muriuki said after the deadline expires, police will mount roadblocks.
He urged operators unwilling to register new saccos to join existing ones.