Lebanese security officials say a string of rockets slammed into a town along the country's border with Syria, killing at least six people, including two children who were out playing.

The officials say the rockets hit the town of Arsal on Friday. The official National News Agency says the attack also wounded 15 people.

It was not immediately clear who fired the rockets but residents in the area say heavy fighting has been taking place on the Syrian side of the border since Thursday.

The Syrian civil war has increasingly spilled over into neighboring Lebanon, where violence from rockets, car bombs and sectarian clashes has claimed dozens of lives in the past year.