The Israeli army said it carried out fresh air strikes against Hamas positions in the Gaza Strip on Saturday, in response to firebombs sent into Israeli territory attached to balloons.
Clashes also broke out in the evening along the Gaza-Israeli border, the army said.
Dozens of Palestinian "rioters burned tyres, hurled explosive devices and grenades towards the security fence and attempted to approach it," the Israel Defense Forces (IDF) said in a statement.
Over the past week Israeli forces have carried out repeated night-time strikes on targets linked to the Islamist group Hamas, which controls the Gaza Strip.
The army says they are in response to the use of makeshift firebombs, attached to balloons and kites, which have been sent into parts of southern Israel, causing thousands of fires in Israeli farms and communities.
There were 19 such Palestinian attacks on Saturday alone, according to Israeli rescue services.
In response "IDF fighter jets and aircraft struck a number of Hamas military targets in the Gaza Strip," the army said in its statement, adding that among the targets hit were "a military compound and underground infrastructure" belonging to Hamas.
Israel has also closed its Kerem Shalom goods crossing with the Gaza Strip and reduced the territory's permitted Mediterranean coastal fishing zone, in response to the recent balloon launches.
Despite a truce last year backed by the UN, Egypt and Qatar, the two sides clash sporadically with rockets, mortar fire or incendiary balloons.
The Gaza Strip has a population of two million, more than half of whom live in poverty, according to the World Bank.
Hamas "is responsible for all events transpiring in the Gaza Strip and emanating from it, and will bear the consequences for terror activity against Israeli civilians," the IDF said in its statement Saturday.