Hamas firing squads Friday publicly executed 18 Gaza Palestinians suspected of collaborating with Israel, a day after three of the Islamist group's top military commanders died in targeted Israeli airstrikes.
Nine men and two women were gunned down at an abandoned police headquarters, witnesses reported. Later, gunmen in black Hamas garb lined up seven hooded men outside a Gaza City mosque and shot them dead as hundreds watched.
The alleged informants were convicted by "revolutionary military trials" of revealing the locations of tunnels, rocket launchers and "resistance houses" that Israel destroyed, the Maan news agency reported.
Hours after the executions, a mortar shell fired from Gaza landed in a small farming kibbutz in southern Israel, killing a 4-year-old boy, the first Israeli child to die in the fighting.
The Israeli military said the shell was launched from beside a U.N. school sheltering Gazans displaced by the fighting, which began July 8. Early Saturday, an Israeli Defense Forces spokesman retracted that claim, saying Hamas, not the U.N., was operating the school, the Jerusalem Postreported.
Prime Minister Benjamin Netanyahu expressed his condolences over the boy's death and vowed that Hamas would pay a "heavy price."
Soon after, jets attacked targets in Gaza, and the military warned residents that more airstrikes were coming.
By early evening, according to the Israeli military, Hamas fighters had fired at least 117 rockets and mortar shells, and at least 35 airstrikes had been conducted in Gaza.
Palestinian health officials said that at least 45 people were wounded in one hit on a house in Gaza City.
Hamas rockets wounded five Israelis and damaged a synagogue. Just before midnight, sirens warning of rocket fire sounded in several Israeli towns near the Gaza Strip.
The renewed attacks came three days after truce talks in Cairo ended in failure.
Nearly 2,100 Palestinians have died in the six weeks of fighting, including 478 children and minors, according to Gaza officials and the United Nations. Two-thirds were younger than 12.
The death toll in Israel stands at 64 soldiers and four civilians.
Contributing: Associated Press