BEIRUT — Fighting erupted along the border between Lebanon and Syria overnight into Monday, Syrian state media reported, after three Syrian soldiers were killed in earlier clashes.

The violence came a month after dayslong fighting between the Syrian military and armed Lebanese Shia groups closely allied with the ousted Bashar Assad government in Syria’s Al-Qasr area.

Lebanon has been seeking international support to boost funding for its military as it gradually deploys troops along its porous northern and eastern borders with Syria and along its southern border with Israel.

The Lebanese and Syrian armies said they are communicating with each other to ease tensions. Lebanese troops have been deployed in large numbers in the area. Families in the border areas fled toward Hermel in Syria amid the overnight clashes and shelling.

Syria’s interim government accused militants from the Lebanese Hezbollah group of crossing northeastern Lebanon into Syria on Saturday, kidnapping three soldiers and killing them on Lebanese soil.

Hezbollah in a statement denied any involvement. The Syrian Observatory for Human Rights, a Britain-based war monitor, said the Shia groups were involved. The circumstances of the incident remain unclear.

Syrian state media, citing an unnamed Defense Ministry official, said the Syrian army shelled “Hezbollah gatherings that killed the Syrian soldiers” along the border.

Though the clashes largely calmed before sunrise, Lebanese media reported low-level fighting at dawn after an attack on a Syrian military vehicle.

The number of casualties remains unclear.

The Lebanese military said it delivered the bodies of the three killed soldiers to their Syrian counterparts.