Jerusalem (CNN) Two Palestinians in Gaza were killed Saturday night in Israeli airstrikes after four Israeli soldiers were wounded by an explosive device along the Gaza border.

The hostilities mark some of the most serious clashes since the end of the 2014 Gaza war

Salem Sabah and Abdallah Abu Sheikha, both 17 years old, were killed Saturday night when the Israeli military carried out a series of air and tank strikes across Gaza, according to the Palestinian Ministry of Health and the Palestinian news agency WAFA.

The strikes hit 18 Hamas targets, including what the Israeli military called an "offensive terror tunnel" in Zaytun in southern Gaza, Israel Defense Forces (IDF) said.

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The strikes were carried out in response to an explosive device that detonated on the Gaza border earlier Saturday, injuring 4 soldiers. Two of the soldiers were severely injured, the Israeli military said. It was not immediately clear who was responsible for that bombing.

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