According to the police, the suspect is a resident of Mannar and was involved in LTTE activities during the war.
He was arrested by the central province anti terrorism police unit over his involvement in the bombing which killed 7 civilians.
The suspect has been handed over to the Kandy police for further investigations.
Seven people were killed on 2006 May 7 as three powerful land mines exploded while a group of tourists were visiting the National Park in a double-cab.
The victims were identified as Darel Perera, Nihal de Silva, Nanadana Abeysuriya, Endista Abeysuriya, Chandi Asirwadan, Anula Asirwadan and Anura Dissanayake.