The Israeli air force continues striking at militant targets in the Gaza Strip on Saturday, as hopes for a ceasefire between Israel and the Hamas-led militant groups appear to dwindle.

According to a statement released by the Israel Defense Forces (IDF), several command centers of the Palestinian Islamic Jihad (PIJ) were targeted in a fresh round of airstrikes on Saturday, with mortar shells and rocket launch sites being hit.

The PIJ has fired almost 1,000 rockets, some deep into Israel, since Tuesday, according to the IDF. No casualties were so far reported in the latest barrage of rockets.

The tit-for-tat fighting has entered a fifth day since it began on Tuesday pre-dawn when Israeli unmanned drones targeted several houses and killed three senior PIJ leaders and some of their family members.

The Palestinian Health Ministry said in a statement on Saturday that Israeli military operations have killed at least 33 Palestinians and injured 147 others, while Israel's Magen David Adom emergency medical service said it has treated 65 Israelis since Tuesday.

An update from the Hamas-run government press office in Gaza said that 17 buildings were destroyed, and a total of 991 housing units were partially damaged or completely leveled.

The streets in Gaza were empty of traffic and pedestrians, while schools, universities, and other official institutions remained closed. Bakeries, pharmacies, grocery stores, and supermarkets were kept open to provide food supplies and medicine to residents in need.

Since the tension flared up, Israel closed the crossing points of the Gaza Strip, mainly the Kerem Shalom commercial crossing point on the borders between the southern Gaza Strip and Israel, and stopped the shipment of fuels, food supplies, and other raw materials to the coastal enclave, home of 2.5 million people.

Salama Maarouf, the spokesman of the Hamas-run government warned that the fuel storage for operating the sole power station would run out within the next day or two, adding that the area would be in full blackout and complete darkness if fuel shipment can't resume soon.

Shiffa Hospital is the main hospital in the Gaza Strip and has been receiving casualties over the past five days, mainly those in severe conditions.

Dozens of people are following up on the medical and health situation of their injured family members at the hospital, expressing dire hope for a stop to this round of fighting.

Efforts to reach a ceasefire between the two sides failed after Israel refused the demand by the PIJ to stop the assassination of its leaders and hand over the body of Khader Adnan, the senior PIJ member who died of a hunger strike two weeks ago in an Israeli jail.

Al-Quds Brigades, the military wing of the PIJ, said in a brief statement that "in the face of the continuation of assassinations and bombings of apartments and houses, the Palestinian resistance will renew its rocket attacks."