The relative calm of a ceasefire between Israel and Hamas has come to an abrupt end with Israel launching dozens of attacks on targets across the Gaza Strip.

Israel said the early Tuesday attacks were launched after Hamas refused to release more hostages held in Gaza. The strikes appeared to end the current ceasefire that took began in mid-January.

A foreign national was killed and four others were wounded in an Israeli airstrike on the site of a United Nations headquarters in central Gaza City on Wednesday, Gaza's health ministry said.