The seizure was made when a bus coming from Pummur in Andhra Pradesh was intercepted at Baipelly checkpost and two unattended bags were found inside the vehicle.
The CISF troops, deployed as part of poll duties in the state, immediately took the bus to Nilanjee police station where it was seized and 1,983 detonators were recovered, a senior official said.
The state goes to assembly polls on May 5.