Jerusalem ? Militants in Lebanon fired at least two rockets into Israel on Sunday, causing no casualties and little damage but raising the possibility of a new flare-up on the volatile border less than a year after Israel’s bloody monthlong war against Hezbollah.

The Lebanese prime minister said the attack was geared at undermining the stability of Lebanon, while the U.N. condemned Sunday’s incident as a serious violation to a cease-fire that ended the conflict last year.

Hezbollah, a Lebanese militant group, denied involvement, and Israeli Prime Minister Ehud Olmert it was mostly likely the work of “a small Palestinian movement.”

Israel’s initial reaction was muted, but security officials were meeting to debate a response.

“We are still clarifying the circumstances,” Olmert said in New York, where he was meeting with U.N. Secretary-General Ban Ki-moon. “Lebanon has been very quiet in the last nine months and hopefully will continue to be so.”

The rockets were the first fired from Lebanon since last summer’s war, when almost 4,000 rockets exploded in Israel. The latest rockets landed in the northern town of Kiryat Shemona, which was hard hit during that conflict.

An official with Olmert indicated Israel would not hit back.