Tunisian authorities have warned of possible car bombings in the capital Tunis and banned traffic in parts of the city after receiving intelligence reports about potential attacks, the state news agency TAP has said.
Sunday's report, based on an interior ministry source, said that a potential assault involving car bombs and attackers with bomb belts had meant to target strategic points in Tunis.
"Orders have been given to intensify patrols and searches by the police and the army in certain parts of the capital and the suburban neighbourhoods," the source said.
Authorities closed off access to the main Avenue Habib Bourguiba in the centre of the city and several other main streets, the agency reported.
State of emergency
Tunisia is under a state of emergency after two deadly gun attacks on tourist sites this year. In March, gunmen killed 21 tourists in an attack at the Bardo Museum in Tunis, and 38 foreigners were killed in an assault on a Sousse beach hotel in June.
Armed groups also often carry out attacks on the military forces in remote areas in Tunisia but have not previously attempted mass killings with car bombs.
More than 3,000 Tunisians have left to fight for armed groups in Syria, Iraq and neighbouring Libya.
Some of them have threatened to return home and carry out attacks on Tunisian soil.
Four years after its uprising ousted President Zine El-Abidine Ben Ali and inspired the "Arab Spring" protests,
Tunisia has a new constitution, free elections and a coalition government with secular and Islamist parties.