BEIRUT , Lebanon ( CNN ) -- Lebanon 's prime minister condemned the firing of rockets into northern Israel after an attack wounded two Israelis on Thursday . He said his government is trying to determine who was responsible . U.N. soldiers on Thursday inspect the site in Lebanon thought to be the source of rockets fired into Israel . Israel 's military warned Israeli civilians to stick close to shelters after police said at least four rockets hit near the city of Nahariya , about 6 miles ( 10 kilometers ) south of the Lebanese border . The Israeli military said it returned fire across the border with mortars . Schools and kindergartens were closed in Nahariya and the nearby town of Shlomi , the Israel Defense Forces reported . `` What happened in the south [ of Lebanon ] is a violation of Resolution 1701 and is rejected by Lebanon , '' Lebanese Prime Minister Fouad Siniora said , referring to the U.N. resolution that ended the 2006 conflict between Israel and Lebanon 's Hezbollah militia . In a statement issued by his office , Siniora said he has asked Lebanese authorities to investigate the attack alongside troops from the U.N. peacekeeping force deployed along the border . He also condemned the Israeli retaliatory strikes , which the Lebanese military said inflicted no casualties . Watch CNN 's Christiane Amanpour discuss rocket attack » . There was no immediate claim of responsibility for the attacks , which came as Israeli airstrikes on Gaza , to the south , entered a 13th day . The Israeli campaign in Gaza is aimed at halting rocket fire from the Hamas-ruled Palestinian territory . Israel fought a similar battle against the Lebanese Shiite Muslim militia Hezbollah in 2006 , during which Hezbollah rained rockets on cities in Israeli 's north for a month before a cease-fire was reached . But Hezbollah has kept a tight rein on its forces in southern Lebanon since the cease-fire , and a number of Palestinian factions operate in southern Lebanon as well . Andrea Tenenti , a spokesman for UNIFIL , the U.N. peacekeeping mission in Lebanon , said the rockets appear to have been fired from a point about 4.5 miles east of Naqoura , where the peacekeepers are headquartered . `` We 've been intensifying our patrols on the ground in order to prevent any further incident , '' Tenenti said . He said UNIFIL 's commander , Maj. Gen. Claudio Graziano , is in `` constant and close contact '' with both sides `` and has urged maximum restraint in order to prevent any escalation of the situation . '' CNN 's Michal Zippori in Jerusalem and Cal Perry and Nada Husseini in Beirut contributed to this report .
NEW : Prime Minister Fouad Siniora calls attack a violation of UN resolution . NEW : Lebanese Army , United Nations resolution , Siniora says . " Lebanon - based rockets strike northern Israel , " news . Israeli military returns fire toward source of rocket attack .