A 30-DAY state of emergency and overnight curfew for the capital have been declared in Tunisia following a suspected suicide bombing of a bus carrying members of the presidential guard.
A government spokesman said at least 12 people had been killed and 20 wounded by the blast.
The bombing followed two terrorist attacks earlier this year that killed 60 people, cruelled the Tunisian tourism industry and rocked confidence in a country that had been seen as a progressive model for the region.
In an address to the nation, President Beji Caid Essebsi said Tunisia was at "war against terrorism" and urged international co-operation in the battle against Islamic extremists.
"I want to reassure the Tunisian people that we will vanquish terrorism," he said.
A popular uprising in Tunisia unleashed democracy movements across the region in 2011.
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