At least 33 suspected Al-Shabaab terrorists were arrested and two planned attacks foiled in Tana River County between December and March.
Deputy County Commissioner Michael Kioni said that last year, security agencies waylaid some 20 Al-Shabaab terrorists traveling by road to attack Jamhuri Day celebrations in Hola town.
Tana River Governor Hussein Dado and County Commissioner Isaiah Nakoru are said to have been the targets, among other senior county and national governments officials.
He indicated that among the attackers were suicide bombers.
In an interview with the Nation, Mr Kioni said police received prior intelligence that helped them to thwart the attack targeting the crowd attending the public holiday.
He said a team of security officers from the military and Anti-Terrorism Police Unit (ATPU) intercepted the group on the Lamu-Garsen road and seized assorted bomb-making materials.