Rockets fired from Lebanon struck northern Israel early Tuesday for the first time in more than two years, drawing a burst of Israeli artillery fire across the tense border, the Israeli military said.
No casualties or major damage were reported on either side, and no one claimed responsibility for the attack. The military said at least two of the rockets landed on Israeli soil, and that Israeli guns shelled the area where the fire had originated.
The U.N. peacekeeping force in southern Lebanon, known as UNIFIL, said it had deployed additional troops and stepped up patrols in the area to prevent any further violence.
UNIFIL's commander, Maj. Gen. Alberto Asarta Cuevas, said in a statement that he was in close contact with Israeli and Lebanese officials. "There is a need to act with restraint and the parties have reassured me of the continued commitment to maintain the cessation of hostilities," he said.
UNIFIL has policed southern Lebanon to enforce a cease-fire that ended a bloody, monthlong war between Israel and the Lebanese guerrilla group Hezbollah in the summer of 2006. Israeli officials said they did not believe Hezbollah was involved in Tuesday's attack.
The flare-up comes at a time when the entire region is engulfed in violence and upheaval, with thousands killed in the regime's crackdown on protesters in Syria and after popular uprisings ousted longtime rulers in Libya, Egypt, Tunisia and Yemen.
The Israeli military said it did not expect Tuesday's incident to touch off a wider conflict with Lebanon. In a statement, however, it said it regarded the attack as "severe" and held the Lebanese government and army responsible for preventing rocket fire at Israel.
A Lebanese security official told The Associated Press that one rocket was fired from Lebanon and that Israel hit back with six rockets, which landed in an empty area. The official spoke on condition of anonymity because he was not authorized to speak to the media.
Israel's Army Radio station said it was the eighth rocket attack since the 2006 war. Hezbollah has not claimed responsibility for any of the attacks, but smaller militant organizations, some Palestinian and some linked to al-Qaida, have launched rockets on several occasions.
None of the rocket attacks has caused serious casualties. But in August 2010, two Lebanese soldiers, a Lebanese journalist and an Israeli soldier were killed in a brief border clash touched off by Lebanese army fire toward an Israeli military base.
Overall, however, the border has been largely quiet but tense since the 2006 war, which was sparked by a deadly cross-border attack by Hezbollah on an Israeli military patrol.
During that fighting, Israel bombed Hezbollah's strongholds and Hezbollah barraged northern Israel with nearly 4,000 rockets.
About 1,200 Lebanese and 160 Israelis were killed in the conflict, which ended with the U.N.-brokered truce that sent thousands of Lebanese troops and international peacekeepers to south Lebanon.
Although the cease-fire agreement forbade Hezbollah to rearm, Israel contends the group has since replenished its arsenal with even more powerful weapons.
Associated Press writer Elizabeth A. Kennedy contributed to this report from Beirut.