Tunisia declares state of emergency after 12 are killed in 'terrorist' bus bomb
Twelve members of the Tunisian presidential security service were killed on Tuesday EPA/MOHAMED MESSARA

A bus carrying members of Tunisia’s presidential guard in the capital Tunis – killing at least 12 and wounding 16 others in what the interior ministry called a ‘terrorist act’.

The blast – on a tree-lined avenue in the centre of Tunis – is the latest in a series of Islamic extremist attacks in the country.

In June, thirty British people died in an attack near Sousse where an Islamist gunman massacred holidaymakers.

Police cordoned off the scene of the attack in central Tunis after the explosion, and ambulances rushed to the scene.

A hooded police officer prevents media from aproaching the scene of a bus explosion in the center of the capital, Tunis, Tunisia, Tuesday, Nov. 24, 2015. An explosion struck a bus carrying members of Tunisia's presidential guard in the country's capital Tuesday, killing at least 12 people and wounding more than a dozen others in what the Interior Ministry called a "terrorist act". (AP Photo/Hassene Dridi)
A hooded police officer prevents media from aproaching the scene of a bus explosion (AP Photo/Hassene Dridi)

President Beji Caid Essebsi was not in the bus at the time. His presidential guard is an elite security force that protects only the president.

Witness Bassem Trifi, a human rights lawyer, said the explosion hit the driver’s side of the bus, describing a “catastrophic spectacle”.

‘I saw at least five corpses on the ground,’ he said. ‘This was not an ordinary explosion.’

Earlier this month, Tunisian authorities announced the dismantling of a cell that it said had planned attacks at police stations and hotels in the seaside city of Sousse, about 150 kilometres (95 miles) south east of Tunis. Sousse was one of the targets of attacks earlier this year.