A senior official with the Hamas militant group that controls Gaza has said he expects a ceasefire with Israel "within a day or two", as cross-border attacks continue.
But Israeli PM Benjamin Netanyahu said on Wednesday he was "determined to carry on" until "calm and security are restored to Israeli citizens".
More than 100 Israeli air strikes targeted Hamas infrastructure in the north of Gaza early on Thursday.
Hamas retaliated with rocket fire.
Fighting began in Gaza after weeks of rising Israeli-Palestinian tension in occupied East Jerusalem that culminated in clashes at a holy site revered by both Muslims and Jews. Hamas began firing rockets after warning Israel to withdraw from the site, triggering retaliatory air strikes.