"The number of martyrs has risen to 30, with another 280 people injured, with the death of Ayman Rafiq Selim from his injuries," spokesman Ashraf al-Qudra said in a statement late Friday.
Selim, who was wounded earlier Friday evening in a strike on the east of Gaza City, was a member of Islamic Jihad's armed wing, the Quds Brigades, the group said in a statement.
Earlier Friday evening, Qudra announced that one Palestinian had been killed and two seriously wounded in a strike on a car in central Gaza, shortly after a raid elsewhere in central Gaza that killed four people.
"One citizen was martyred and two others seriously injured in an Israeli strike on a car in Deir al-Balah," Qudra said.
"Three citizens were martyred in a strike in Maghazi camp and their bodies were taken to Shuhada al-Aqsa Hospital," he told AFP, adding subsequently that a fourth man was killed in the same strike.
Security sources named one of the dead as Ahmed Abu Jalal, a field commander of Hamas's armed wing, the Ezzedine al-Qassam Brigades.
Qudra added that the strike, in the central Gaza Strip, targeted a home and that two of those killed were brothers.
Throughout Friday evening, air strikes continued to pound towns throughout Gaza, including across Gaza City.
In the city's Tel al-Hawa neighbourhood, eyewitnesses reported that an interior ministry administrative building already targeted in earlier raids had been hit again, and the emergency services reported damage to a clinic in the same area.
At a press conference at Gaza City's Shifa hospital on Friday night, Hamas health minister Mufid al-Mukhalalati warned of "an acute shortage of medicine and medical supplies."
He urged "Arab countries and all parties to support the health sector," thanking Egypt for the help it has already offered.
Since Israel's targeted killing of a top Hamas military chief on Wednesday afternoon, rockets fired from Gaza have killed three Israelis and injured 16, police and medics said.(AFP)