Israel's military said it carried out retaliatory airstrikes on the Gaza Strip on Thursday night, in the second consecutive day of cross-border violence.
An Israeli military spokesperson said in a statement that an attack helicopter struck an infrastructure in the northern Gaza Strip used for underground activities of Hamas, an Islamist Palestinian movement that runs Gaza.
It said the strike was in response to explosive balloons launched earlier on Thursday from the Palestinian enclave into Israeli territory.
Local media reported that the balloons exploded near a military patrol in the vicinity of the fence separating Israel and the besieged enclave. There were no reports of injuries or damage.
On Wednesday night, Israeli fighter jets struck a weapons manufacturing place and a military compound belonging to Hamas in Gaza after four rockets were fired into Israel.
It was not clear which group fired the rockets but the military said it held Hamas accountable for any hostility form Gaza.
The violence came after a month of relative calm as result of the international efforts led by Egypt and the United Nations to achieve an unofficial cease-fire between Israel and Hamas.