Syria says that an attack which killed at least 17 people in the capital Damascus on Saturday was carried out by a suicide bomber in a car which entered the country from an Arab neighbour the previous day.
The reports in the Sana news agency and on state television on Sunday did not name the country but Syria shares borders with three Arab countries - Lebanon, Iraq and Jordan.
The vehicle, packed with 200kg of explosives, was blown up near a Syrian security installation on the southern outskirts of the capital. It was the biggest attack in the country since the 1980s.
"Investigations showed that a terrorist was driving the car and blew himself up and the car. Confirmation of his identity is under way via a DNA examination of the remains of his corpse," the news agency said.
The Sana news agency said that the attacker belonged to a group which urges Sunni Muslims to kill anyone who does not share their beliefs. It said members of the group had previously been arrested by security forces.
No group has claimed responsibility for the attack, but several people have reportedly been detained in connection with the bombing.
Bashar al-Assad, Syria's president, recently said that "extremist forces" were operating in northern Lebanon and looking to destabilise Syria. About one week ago Syria massed troop along the border with its neighbour.
Hisham Jaber, a military analyst and retired Lebanese general, told Al Jazeera that the blast could be linked to an attack on Lebanese troops in the northern city of Tripoli on Monday.
|At least 17 people died and several others were injured in the blast [AFP]
"The same side is doing, in my opinion, the two explosions which we can say are 100 per cent a terrorist operation," he said. "I wouldn't say the same section, or same section, but the same side."
Al Jazeera's Hashem Ahelbarra, reporting from Damascus, said that it was also possible that the attacker was from a group operating out of Iraq.
"Syria share 800km of borders with Iraq, these borders have been described by Western diplomats as porous ... that is why America was psuhing Syria to beef up patrol units," he said.
The bombing was the third security incident in Syria this year.
In February, the military commander of the Lebanese Hezobollah movement was assassinated in Damascus. Then in August, Syria confirmed that Mohammed Sleiman, a general described in the Arab media as Damascus's liasion with Hezbollah, had been shot dead.