A bomb exploded near an Israeli military patrol along the border with Gaza on Saturday afternoon, leading to an exchange of gunfire that lasted into the night.
Four Israeli soldiers were injured when a booby-trapped Palestinian flag exploded as they stopped to examine it during a routine patrol. One of the gravely wounded soldiers was a squadron commander in the Corps of Engineers.
In response, an Israeli tank targeted an observation point belonging to Islamic Jihad, one of the militias active in the Gaza Strip.
Israel Defense Forces spokesman Brig. Gen. Ronen Manelis said Israel holds the Gaza Strip's ruling paramilitary group, Hamas, responsible for everything occurring in the Strip.
A few hours later, incoming rocket warning sirens rang out in several communities on Israel's southern border as projectiles were launched from Gaza. One rocket hit a home in the kibbutz, or communal village, of Sha'ar HaNegev but failed to detonate.
No Israeli casualties were reported but two residents were taken to a hospital.
The Israeli army said it retaliated with a "large-scale attack" that hit six Hamas targets, including two military bases and a tunnel from Gaza into Israel.
The Israeli army believes the coalition of militants belonging to various Islamist factions calling itself the Popular Resistance Committees in Gaza hung the flag at the border with the intent of luring Israeli soldiers who patrol the area.
In a statement, the Popular Resistance Committees described the bomb as "a heroic act in response to the enemy's infiltration into the Gaza Strip."
Saturday's flare-up is typical of the pattern established since the 2014 cease-fire between Israel and Gaza, in which the militant provocations from the Strip result in immediate but limited retaliations from the Israeli side, but it also exemplifies the line's volatility.
The region has seen a marked increase in violence since President Trump's December announcement that the U.S. would recognize Jerusalem as Israel's capital, with Friday protests at the border and in the West Bank becoming a regular feature. There were also clashes Saturday between Israeli forces and Palestinians.
The Israeli army believes the flag was hung during a Friday demonstration in which the Palestinian Health Ministry reported over 20 Palestinians were wounded.
The Israeli army's chief of staff, Gen. Gadi Eisenkot, recently warned of the dangers posed to Israel by the rapidly deteriorating humanitarian situation in Gaza — blockaded by Israel and Egypt and punished by the Palestinian leadership based in Ramallah, which has been mired in discord with Hamas.
Tarnopolsky is a special correspondent.
3:55 p.m.: This article was updated throughout with staff reporting.