JERUSALEM ( CNN ) -- The United Nations has condemned Friday 's rocket attack on Israel from southern Lebanon , and urged both sides `` to exercise maximum restraint . '' Italian soldiers with UNIFIL and Lebanese security forces inspect a rocket site in Qlayleh , Lebanon , on Friday . Israel 's military fired between 12 and 18 artillery shells into southern Lebanon Friday shortly after the rocket attack on northern Israel , according to the Israeli military and a Lebanese army official . There were no casualties in either incident . Rockets fired from Lebanon struck open spaces in the western Galilee region of northern Israel , an Israel Defense Forces spokesman said . There were no reports of damage . Israel retaliated by firing toward the source of the rocket fire , the IDF spokesman said . The shells landed near the southern Lebanese village of Qlayleh around 3 p.m. ( 8 a.m . ET ) , a Lebanese army official said . The IDF spokesman said the Israeli military considers the rocket-fire incident to be serious and holds Lebanon 's government and military responsible . Israel Radio reported one rocket struck near the northern town of Nahariya and another landed near Gesher Haziv , a kibbutz , or collective community . Israeli police spokesman Micky Rosenfeld said residents near Nahariya heard several explosions , and the remnants of at least one rocket were found . There has been no immediate claim of responsibility for the attack . U.N. Secretary-General Ban Ki-moon released a statement through his spokeswoman , condemning the attack . He said the United Nations mission in Lebanon , UNIFIL , `` is investigating the circumstances of the incident in close cooperation with the Lebanese Armed Forces . '' There are an estimated 30,000 rockets in southern Lebanon , all under the control of Hezbollah militants . Israel fought a war against Hezbollah militants in Lebanon three years ago that is widely regarded as having empowered the Shiite militia . CNN 's Michal Zippori in Jerusalem and Nada Husseini in Beirut , Lebanon , contributed to this report .
NEW : It urges Lebanese , Israelis ` ` to exercise maximum restraint '' Israel says rockets fired from Lebanon hit open spaces in northern Israel . Israel says it fired 12 to 18 artillery shells into southern Israel in retaliation . There have been no injuries , and no one has claimed responsibility for rocket attack .