Neighborhood wellbeing authorities said a little kid was among the dead with many others injured.
Israel's PM said the activity followed "a quick danger" by Palestinian Islamic Jihad (PIJ) after the capture of one of its individuals early this week.
The PIJ terminated in excess of 100 rockets into Israel "in an underlying reaction".
Most were captured by Israel's Iron Dome rocket safeguard. Alarms were heard in various Israeli urban communities.
The Israel Defense Forces (IDF) said it then continued strikes late on Friday, focusing on aggressor positions.
In a broadcast address prior in the day, Israeli Prime Minister Yair Lapid said "Israel did an exact counter-fear activity against a quick danger".
The IDF said it struck destinations connected to the PIJ. They incorporate the skyscraper Palestine Tower in Gaza City, hit in a boisterous blast which left smoke pouring from the structure.
Four PIJ aggressors - including Tayseer Jabari - and a five-year-old young lady were among those killed since the strikes began, neighborhood wellbeing authorities say.
They say another 55 individuals were harmed.
An Israeli military representative said the IDF was "expecting to be around 15" assailants had been killed.
Israel's Interior Minister Ayelet Shaked told Channel 12 News: "We don't have the foggiest idea how this will work out… yet this could take time… This could be an extensive round [of conflict] and a hard one."
Talking while on a visit to the Iranian capital, Tehran, PIJ secretary general Ziyad al-Nakhala said "we will answer powerfully to this hostility, and there will be a battle in which our kin will win".
"There are no red lines for this fight... furthermore, Tel Aviv will be under the rockets of the opposition."
In the mean time, Hamas, which oversees the Gaza Strip, said that furnished gatherings were "joined together" in fight and wouldn't stay quiet.
On Monday night, Israel captured Bassem Saadi, answered to be the head of PIJ in the West Bank. He was held in the Jenin region as a feature of a continuous series of capture tasks after a flood of assaults by Israeli Arabs and Palestinians that left 17 Israelis and two Ukrainians dead. Two of the assailants came from the Jenin region.
After Bassem Saadi's capture, Israel uplifted safety efforts for networks close to its boundary with Gaza, advance notice that PIJ expected to go after regular folks and troopers. Street terminations got towns and towns southern Israel to a crushing stop.PIJ, which is upheld by Iran, has its base camp in Damascus, Syria, and is quite possibly of the most grounded aggressor bunch in Gaza. It has been liable for some assaults, including rocket-fire and shootings against Israel.
Israel and PIJ battled a five-day struggle in November 2019 in the wake of battling emitted following the killing by Israel of a PIJ commandant who Israel said was arranging an impending assault. The viciousness left 34 Palestinians dead and 111 harmed, while 63 Israelis required clinical treatment.
Israel expressed 25 of the Palestinians killed were aggressors, including those hit getting ready to send off rockets.