BEIRUT — Attackers detonated a roadside bomb against a passing army truck near the Syrian border Friday, killing two soldiers and wounding three in the latest spillover from the civil war next door.

The violence appeared to be the latest in tensions between Lebanese troops and Syrian Islamic extremist rebels crossing the border in a spillover of Syria's civil war. The bomb exploded Friday near the army patrol outside the border town of Arsal, an area of repeated clashes, security officials said, speaking on condition of anonymity in line with regulations.

Prime Minister Tammam Salam blamed jihadi extremists for the bombing in a statement by his office. Officials said earlier that that attack was a rocket but later said it was a roadside bomb. Salam's statement and state-run National News Agency also said it was a bomb.

The attack came after the army detained a Lebanese and two Syrians alleged to be part of a "terrorist cell" near Arsal. On Wednesday, jihadi gunmen crossed from Syria and snatched a Lebanese solider. Gunmen snatched around 20 soldiers and police in August.

At least eight of the soldiers are being held by the Syrian al-Qaida affiliate, the Nusra Front. Others are being detained by the extremist Islamic State group, which has beheaded two. The killings outraged Lebanon and sparked days of violence against Syrian refugees in the country. Since the abductions, Lebanese troops have clashed repeatedly with jihadi fighters near Arsal.

Police on Friday were questioning three Syrians who entered the country illegally on suspicion of a connection to the beheading of one of the soldiers, security officials said.

The Islamic State group, which controls parts of Syria and Iraq, has also beheaded two Americans and a British citizen in recent weeks.