BEIRUT (Reuters) - A ceasefire in a Syrian town near the Lebanese border and two villages to the north has broken down after renewed shelling, the Syrian Observatory for Human Rights monitoring group said on Saturday.

The truce between the Syrian army and the Lebanese group Hezbollah on the one side, and Syrian insurgents on the other, came into effect in the western town of Zabadani and the Shi'ite Muslim villages of Kefraya and al-Foua in the northwest on Thursday.

It had been extended late on Friday but had collapsed by the morning, said Rami Abdulrahman, who runs the Britain-based Observatory.

Local ceasefires in Syria's four-year conflict have tended to be fragile, and U.N. attempts to forge larger truces in other parts of the country, such as in the northern city of Aleppo, have come to nothing.

Zabadani has been at the center an offensive by Hezbollah and the Syrian army against insurgent groups. The area is important to the Syrian government because of its proximity to the capital Damascus and the Lebanese border.

The two villages, in the province of Idlib, have been under attack by insurgent groups. The area borders Turkey and is mostly rebel-controlled after advances against the military this year.

The sides in negotiations had discussed evacuating the wounded from the three areas under the ceasefire but so far none have been transported out, the monitoring group said.

(Reporting by Sylvia Westall; editing by John Stonestreet)