The Israeli military struck targets in the Gaza Strip late Thursday, after incendiary balloons were launched from the enclave earlier in the day.
A military statement said a helicopter had attacked an underground facility used by Hamas.
On Wednesday night, Israeli fighter jets struck Hamas posts in Gaza after four rockets were launched at Israel.
The last time Palestinians fired rockets at Israel was some three weeks ago, when Prime Minister Benjamin Netanyahu was attending an election campaign event in the southern port city of Ashkelon.
The rocket fire forced Netanyahu to leave the stage mid-speech and seek shelter; he later returned to complete the address. The Iron Dome missile defense system had intercepted one rocket at the time.
In retaliation, the Israel Defense Forces struck in the Strip, hitting Hamas targets in the Strip. Among the targets struck were military compounds used by the group.
Earlier in December, Israeli aircraft bombed several militants’ sites in Gaza, hours after three rockets were fired from the Palestinian enclave toward southern Israel.