Rockets from Lebanon struck northern Israel on Sunday, causing no injuries but sparking an Israeli reprisal shelling in a rare flare-up between the two countries.
Residents of the northern Israel town of Kiryat Shmona awoke to a pair of large explosions. Israeli police spokesman Micky Rosenfeld said no injuries or damage were caused from the rocket fire. Shortly after, the Israeli military said it responded with artillery fired toward the source of the launch.
Lebanon's state news agency said the border area was shelled after the rockets hit Israel. The agency said over 20 shells hit the mountainous region around the southern Lebanese border area of Rachaya.
Israeli Defense Minister Moshe Yaalon said Israel "would not tolerate" such attacks and held the government and army of Lebanon responsible for any fire emerging from its territory.
"We will not allow incidents such as those of this morning to pass quietly," he said in a statement. "I would not recommend to anyone to test our patience and our determination to protect the security of the people of Israel."
The Israel-Lebanon border has remained mostly quiet since a monthlong war in the summer of 2006 between Israel and Hezbollah guerrillas in Lebanon. There have been sporadic outbursts of violence, most recently earlier this month when a Lebanese army sniper killed an Israeli soldier.
In the most serious incident, Lebanese forces killed a high-ranking Israeli officer in 2010 and Israel responded with artillery fire that killed three Lebanese. However, incidences of rocket fire have been infrequent since the countries agreed to a cease-fire that ended the 2006 war.
The 2006 war broke out after Iranian-backed Hezbollah guerrillas crossed into Israel and captured two Israeli soldiers. The ensuing monthlong conflict killed about 1,200 Lebanese and 160 Israelis.
Israel and Lebanon have fought several wars before. In 1982, Israel invaded Lebanon with the stated intention of driving Palestinian guerrillas out of the south. The Israeli military battled halfway through the country into Beirut and occupied south Lebanon until 2000.
Given the years of enmity between the two countries, even the smallest incident raises the risk of sparking a wider conflagration.
Lebanon is unusually jittery after a Friday car bombing in an upscale district of Beirut. On Sunday, Lebanese soldiers fanned out throughout the country, manning checkpoints and closing off sensitive roads.
Nonetheless, the Lebanese government is notoriously unable to control its own security. Hezbollah has its own large, well-trained militia that dominates the southern border. There are also small bands of Palestinian militants who claim responsibility for some isolated rocket attacks.
There has yet to be a claim of responsibility for Sunday's unprovoked rocket attack.