Palestinian Arab terror teens from the Democratic Front for the Liberation of Palestine (DFLP) fire a mortar shell during a military graduation ceremony in Rafah in southern Gaza. Service resumed about two hours later.
Israel has been constructing a sensor-equipped underground wall along the 60-km (36-mile) Gaza border, aiming to complete the $1.1 billion project by mid-2019.
No injuries were reported on either side of the fence dividing the Gaza Strip from Israel.
"We remain ready with the tools necessary and the capabilities at hand should Hamas or the Islamic Jihad act aggressively again".
In the immediate wake of the incident, he added, air-raid sirens were sounded in Israeli towns situated close to Gaza's borders.More news: Year's brightest supermoon coming to OR skies Sunday night
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The exchange came exactly one month after Israeli forces destroyed an attack tunnel belonging to the Palestinian Islamic Jihad group, in which at least 14 terrorists were killed, including two of the organization's top commanders.
The IDF later said they had used tanks and aircraft to attack four terror targets located in Gaza Strip in response to the mortar shells fired at an adjacent military outpost on the northern border.
The U.N. envoy for the Middle East peace process meanwhile held meetings in the Gaza Strip as part of efforts to urge Hamas and rivals Fatah to follow through on their landmark reconciliation accord mediated by Egypt. Hamas has rejected the demand.
Fayez Abu Eita, a spokesman for Fatah in Gaza, said the same in remarks after the factions met in Gaza City, noting it was in the interest of "achieving the goals of our people, achieving reconciliation and ending the division".