BEIRUT — Suicide bombers killed five people and wounded at least 15 in a northwestern Lebanese village near Syria on Monday, witnesses and paramedics said.

The attack took place in the mainly Christian village of Qaa, a few hundred yards from the frontier. The state-run National News Agency said four suicide bombers participated. No group immediately claimed responsibility.

Violence from the Syrian civil war has spilled over the border in the past, inflaming Lebanon’s own political divisions and raising concerns over the more than 1 million Syrian refugees there, who now make up a fifth of the tiny country’s population. The nationalities of the attackers remained unknown.

An eyewitness said the four attackers raised suspicions when they passed through the village before dawn. When civilian village guards called out to them, they threw a hand grenade. The witness spoke on condition of anonymity for fear of retribution.

Mayor Bashir Matar said residents began gathering after the first explosion and the other bombers targeted the crowd, one after the other.

‘‘As we were treating some of the wounded, I saw the fourth suicide attacker coming toward me. I shouted at him,’’ Matar told the Al-Mayadeen TV network. ‘‘We opened fire toward him and he blew up.’’

George Kitane, head of paramedics at the Lebanese Red Cross, confirmed the death toll and said the 15 wounded were taken to nearby hospitals. One of the explosions struck an ambulance, killing its driver, residents said.

Qaa and the nearby Ras Baalbek are the only two villages with a Christian majority in the predominantly Shi’ite Hermel region.

Associated Press