Tunisia has declared a state of emergency after an explosion on a bus that was carrying the president's security guard through the heart of the capital Tunis, killing at least 12 people.
According to the New York Times, Tunisian President Beji Caïd Essebsi said that the explosion was a "cowardly terrorist attack."
Essebi cancelled a scheduled trip to Switzerland and announced a nightly curfew.
According to reports, the Tunis airport and tourist sites were shut down after the explosion.
Essebsi said that 20 members of the presidential guard had been wounded.
No group has claimed responsibility for the attack as yet.