Israel carried out strikes against bases in the Gaza Strip on Tuesday after Palestinians launched their heaviest barrages against Israel since the 2914 Gaza war.
The firing of some 28 mortar shells toward Israel caused no injuries, with most intercepted by air defense systems, but Prime Minister Benjamin Netanyahu vowed a forceful response.
"Israel takes a grave view of the attacks on it and its communities by Hamas and Jihad from the Gaza Strip,” he said during a conference in northern Israel, adding that the military would respond “forcefully.”
One mortar shell exploded near a kindergarten building, a military spokesman said, causing damage to the structure.
Shortly after Netanyahu spoke, Israel's military began carrying out strikes in Gaza.
Israel's military said it was "currently operating in the Gaza Strip. The explosions heard are related to this activity. Details to follow."
It did not confirm whether the response was air strikes, other means such as tank or missile fire or a combination. Gazan sources spoke of air strikes.
Tuesday's incidents came after weeks of deadly demonstrations and clashes along the Gaza-Israel border, beginning on March 30. Tensions have been spiraling along the border with protests struggling to challenge the 11-year blockade of the Gaza Strip and to press Palestinian claims to lands in what is now Israel, which has responded to certain events with airstrikes against military targets in Gaza.
The protests have called for Palestinians who fled or were expelled in the 1948 war surrounding Israel's creation to be allowed to return to their former homes now inside Israel.
They peaked on May 14, when at least 61 Palestinians were killed as tens of thousands of Gazans protested and clashes erupted on the same day of the US transfer of its embassy in Israel from Tel Aviv to Jerusalem.
Demonstrations and clashes have continued at a low level since then. At least 121 Palestinians have been killed by Israeli fire in the unrest.
Israel says its actions are necessary to defend its borders and accuses Hamas of encouraging thousands of Palestinians to break through the border and attack Israelis.
It has fought three wars with Hamas since 2008.
But Israel has faced international criticism and calls for an independent investigation over its use of live fire during the protests and clashes along the border.
No Israelis have been killed and only one soldier has been reported lightly wounded.