Israeli tank fire at an observation post killed three Palestinians in the southern Gaza Strip on Sunday, Palestinian officials said.

The incident happened east of the city of Rafah in the southern Gaza Strip, a spokesman for the health ministry in the Palestinian enclave said.

The ministry identified those killed as Hussein al-Amour, 25, Abdul Haleem al-Naqa, 28, and Marwan al-Amour, 25.

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A statement from the armed wing of Islamic Jihad, the Al-Quds Brigades, claimed two of them as members. It was not yet clear if Marwan al-Amour, who died from his wounds later in the day, was also a member.

Islamic Jihad is the second-most powerful armed group in the Gaza Strip after Hamas, which runs the blockaded Palestinian enclave.

Israel's military said in a statement that the tank fire came after soldiers detonated an explosive device that had been placed near the border fence, targeting its troops. It said the device had been hidden inside a pair of fence cutters.

Separately on Saturday night, Israeli aircraft struck two targets belonging to Hamas, but there were no reports of casualties. The military said the operation was in response to a brief incursion across the border earlier in the day by Palestinians who immediately fled back into Gaza.

It added that the strike was also in retaliation for repeated Palestinian attempts to damage the border fence and “security infrastructure” during ongoing border protests.

At least 119 Palestinians have been killed by Israeli fire in the Gaza Strip since mass protests and clashes broke out on March 30, according to figures from the Gazan health ministry.

No Israelis have been killed during that time.

Low-level demonstrations along the border have continued since protests peaked on May 14, when at least 61 Palestinians died as tens of thousands of Gazans protested and clashes erupted over the US moving its embassy from Tel Aviv to Jerusalem.

Israel says its actions are necessary to defend the border and stop mass incursions into its territory. It accuses Hamas, with whom it has fought three wars since 2008, of seeking to use the protests as cover to carry out violence.