Relatives who rushed to a Gaza City hospital said Ibrahim Mansour, 26, was collecting gravel to sell from his donkey cart when he was shot dead. The Israeli military said soldiers fired at Palestinians tampering with Israel's border security fence.
"The soldiers took action in order to distance the Palestinians from the fence. They called on them to stop and fired in the air. When that did not help, they fired at the main instigator," an Israeli military spokesman said.
He said that since the beginning of the year, three explosive devices were detonated against Israeli forces patrolling the fence.
The Islamist Hamas group, which runs the Gaza Strip, and other Palestinian factions have voiced commitment to a ceasefire reached with Israel in 2012, but have cautioned that Israeli "violations" could cause the truce to collapse.
Israel's army said on Twitter that 28 rockets were fired from Gaza in January alone. Israel has mounted air strikes against militants it holds responsible for such attacks.
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