Israeli airstrikes flattened homes in Gaza and Palestinian rocket barrages into southern Israel persisted for a second day, raising fears of another major escalation in the Mideast conflict.
Gaza's health ministry said 24 people had been killed so far in the coastal strip, including six children.
The fighting began with Israel's killing of a senior commander of the Palestinian Islamic Jihad militant group in a wave of strikes Friday that Israel said were meant to prevent an imminent attack.
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So far, Hamas, the larger militant group that rules Gaza, appeared to stay on the sidelines of the conflict, keeping its intensity somewhat contained.
Israel and Hamas fought a war barely a year ago, one of four major conflicts and several smaller battles over the last 15 years that exacted a staggering toll on the impoverished territory's 2 million Palestinian residents.
Whether Hamas continues to stay out of the fight likely depends in part on how much punishment Israel inflicts in Gaza as rocket fire steadily continues.