An Israeli tank fired into the Gaza Strip on Tuesday, killing a Hamas militant in what the army described as retaliation for the wounding of a soldier and a brief incursion during a violent Palestinian border protest.
Palestinian medics in Gaza said another two Hamas militants were hurt in the Israeli shelling of a lookout post near the fortified frontier in the central sector of the enclave ruled by the Islamist group.
Hamas confirmed the three Palestinian casualties as its members.
The border has simmered since Palestinians launched weekly demonstrations last March to press for the lifting of an Israeli-led blockade on the impoverished territory and rights to family lands lost to Israel in the 1948 war of its foundation.
Gaza's health ministry has said more than 220 Palestinians have been killed by Israel during the protests. Israel says its troops have resorted to lethal force to prevent border breaches by Hamas, against which it has fought three wars since 2008.
Earlier on Tuesday, the army said in a statement, one of its officers was shot at as he faced Palestinian rock-throwers at the fence. The bullet struck his helmet, lightly injuring him, the army said, adding that during the incident two Palestinians also crossed into Israel before returning to Gaza.
Worried about a potential flare-up into full conflict, Egypt and the United Nations have sought to calm Gaza while Qatar in November pledged $150 million in donations over six months in hope of easing economic pressure.
A third Qatari payout was due on Wednesday, after it was previously held up by Israel in protest at border violence, Doha said on Sunday. It was not clear if Tuesday's violence would prompt another delay.