The Islamic State on Wednesday confirmed it was behind the attack in Tunsian capital Tunis that killed 13 members of the presidential guard on Tuesday night. The explosion took place at a bus stop and a backpack or belt containing 10kg of military explosives was used, Tunisia’s interior ministry said. The military group released a message on social media, saying one of its suicide bombers had perpetrated the attack, the third time they have targeted the country this year, BBC reported. However, authorities were having difficulty ascertaining the exact sequence of events as part of their inquiries. It is unclear whether the bomber was already on the bus, or the attacker was merely standing close to the spot where the bus usually picks up and drops off members of the guard. AP reported that the suspect bomber’s body was found at the scene of the blast.

The country has declared a state of emergency for a month, and curfew had been imposed in the capital following the attacks. Tunisia has closed its borders with Libya and has reinforced the surveillance of maritime borders and in airports, Al Jazeera reported. The president’s office also announced that the country will hire 6,000 personnel for its security forces to protect itself from radicalised Tunisians returning from Syria. Tunisia has faced several threats from militant groups, since thousands of its citizens joined the war in Syria, on the side of ISIS as well as other fronts.