Prospects of a cease-fire between Israel and its foes Hamas and Hezbollah ran aground on Friday as Israeli airstrikes killed at least 68 people in the Gaza Strip, according to medics in the Palestinian enclave, and bombed Beirut's southern suburbs.

The Israeli military said it killed senior Hamas official Izz al-Din Kassab in an airstrike in the southern Gaza town of Khan Younis and described him as one of the last surviving high-ranking members of Hamas responsible for coordinating with other groups in Gaza.

U.S. envoys had been working to secure cease-fires on both fronts ahead of the U.S. presidential election next Tuesday.