US Secretary of State John Kerry met UN chief Ban Ki-moon in Cairo, and more high-profile talks will be held later.Meanwhile, Israeli media have quoted the army as saying a soldier hit in a Hamas attack on Sunday is missing. Media say he is presumed dead.Nearly 600 Palestinians and 29 Israelis have died in 14 days of fighting.The majority of Palestinians killed were civilians, including dozens of children, according to the UN.Israel says it has killed at least 170 militants.Early on Tuesday, Israeli air strikes destroyed several mosques and targeted a stadium and the home of the late leader of Hamas's military wing.Meanwhile, Israel announced that two more members of the Israel Defense Forces (IDF) had been killed, taking the number of soldiers killed in fighting to 27. Two civilians have also died.'Spare civilians'After the talks with Mr Ban, John Kerry said the US was concerned about Palestinian casualties, but lent his support to Israel's "appropriate and legitimate" military operation.Mr Kerry also said the US was sending $47m (£28m) in aid to Gaza "to alleviate the immediate humanitarian crisis".America's top diplomat arrived in Egypt on Monday and is expected to stay in Cairo until at least Wednesday for talks with top Egyptian officials and the Arab League chief Nabil al-Arabi.Gaza tunnelsConstructed by Palestinian militants under Israel's high-security border fence with GazaIsrael says dozens of tunnels exist which are used by Hamas to carry out attacksTunnels are reinforced with hundreds of tons of concrete and have electricity and provisions to last occupants monthsIsrael says tunnels are interconnected, with passages leading to rocket launchers, command and control centres and in some cases mosquesTunnel was used to capture Israeli soldier Gilad Shalit in 2006Longest tunnel, found in March 2014, in excess of 1.7km (1 mile)lineMr Kerry urged Hamas militants to "make the decision to spare innocent civilians", a call echoed by Mr Arabi, who said the group should accept an Egyptian proposal to end the fighting.Hamas rejected that proposal last week, with its armed wing saying agreeing to it would amount to "surrender".The UN Security Council has issued a call for an "immediate cessation of hostilities", but did not endorse a strongly worded draft resolution backed by Arab states.Mr Ban reiterated the call for an immediate ceasefire ahead of travelling to Israel for talks with Prime Minister Benjamin Netanyahu and meetings with Palestinian officials in the West Bank.Mr Ban said he appreciated Israel's right to defend itself, but said restrictions on Gaza should be lifted "so that people should not resort to this kind of violence as a way of expressing their grievances".Israel launched its ground operation in Gaza after days of air strikes, following rocket fire by militants into Israeli towns.It says the move is necessary to target Hamas' network of tunnels, which have been used by militants to get into Israel and carry out attacks.'Identification process'On Tuesday, the IDF said efforts were under way to identify the last of seven of its soldiers killed in Shejaiya, near Gaza City, on Sunday.The troops are all believed to have died when their armoured personnel carrier was attacked.In a statement, the IDF said "the identification process of six of the soldiers killed has been completed and confirmed"."The efforts to identify the seventh soldier are ongoing and have yet to be determined."Hamas said on Sunday evening that it had captured an Israeli soldier, but Israel's UN ambassador denied the claim.(BBC)Bakudaily.az