Israeli aircraft attacked Hamas sites in the Gaza Strip on Sunday night, a Palestinian security source told AFP after Israel reported three rockets fired at its territory.
The Israeli military said that its aircraft attacked "underground infrastructure belonging to the Hamas terror organisation" in response to the rocket fire.
"Earlier tonight, three rockets were fired from the Gaza strip at Israel," it said in an English-language statement.
"In response... attack helicopters and fighter jets targeted Hamas terror targets."
There were no immediate reports of casualties from either side.
An earlier army statement gave no indication of where the first two rockets fell, but Israeli media said they hit open ground.
The army said that the Iron Dome missile defence system intercepted a third rocket.
There was no immediate claim of responsibility for the rocket launches from the Hamas-run strip.
The Islamist organisation warned Israel in late June that its planned annexation of parts of the occupied West Bank amounted to a "declaration of war".
Two rockets were fired the next day at the Jewish state from Gaza, triggering a punitive Israeli air raid on Hamas installations in the Palestinian enclave.
On July 1, Hamas fired a volley of rockets into the sea as a warning to Israel not to go ahead with annexation, sources in the Islamist organisation told AFP.
Israel's proposal to annex its settlements in the West Bank and the Jordan Valley forms part of a broader US peace plan released in January.
The proposals foresee the ultimate creation of a Palestinian state on the remaining West Bank territory and the Gaza Strip.
But the plan falls far short of Palestinian aspirations, with a state on reduced territory and without east Jerusalem as its capital.
Hamas and Israel have fought three wars, with the latest conflict in 2014 killing 2,251 Palestinians and 74 people on the Israeli side.