The suspects had infiltrated Tunisia from Libya "and their targets were tourism and industrial zones," the minister told local radio stations.
"They were arrested, and mines, explosive belts and explosives were seized," Ben Jeddou said.
An interior ministry spokesman said 16 suspects were arrested in the southern town of Ben Guerdane near the porous border with Libya, with three of them detained early today.
Since late 2012, security forces have been battling dozens of militants hiding out in the remote Mount Chaambi region, near the Algerian border, where eight soldiers were killed in an ambush last July.
Also Read
Last year, more than 20 security personnel were killed in what the government says were "terrorism-related incidents."
Two opposition politicians were also assassinated in separate attacks that plunged the country into crisis.
Last month, Tunis designated Mount Chaambi and neighbouring mountain districts a closed military zone, and warned of the growing threat posed by "terrorist organisations" based there.
Prime Minister Mehdi Jomaa today insisted that the authorities are capable of "undermining the plans" of armed groups, but warned that battling jihadists would lead to as "heavy human losses as anywhere else in the world."