Four Palestinians were killed as the IAF fired missiles at targets in the Gaza Strip overnight Saturday.
Three were killed in a strike on a car in Gaza City, while one died as aircraft hit a three-person squad in Jabalya that had just fired a rocket at a community in southern Israel, Palestinian security and medical officials said.
The IDF said the targeted vehicle was carrying three Hamas operatives and a stack of weapons.
Aircraft also struck Hamas weapons workshops in Gaza City and the northern Gaza town of Beit Lahiya, and a third workshop belonging to Islamic Jihad operatives in the central town of Nusseirat, the IDF said.
No casualties were reported in those three attacks.
Separately, IAF aircraft fired missiles at a Hamas vehicle in Gaza City, but missed, Hamas said. A bystander was injured, Palestinian medical officials said.
The army confirmed an air attack on three Hamas activists, and said it identified a hit. It could not immediately say whether a car had been targeted.
On Saturday morning and Friday night, the IAF carried out several targeted attacks on Hamas installations throughout the Gaza Strip destroying several weapons-making facilities and killing at least three people.
Several minutes after Kassams landed in Sderot Saturday morning, IAF aircrafts shot at the unit that launched the rockets.
Palestinian sources claimed the unit members were unharmed and that the IAF strike hit civilians. The IDF said the launching unit was clearly identified and furthermore, that the air force was operating in an area where Palestinian civilians were clearly warned beforehand not to enter.
IAF fires two missiles at Hamas installation
IAF strikes rocket launching cell as Kassams pound Sderot
Earlier Friday night, just before 3 a.m., the air force struck two factories which the IDF spokesperson said were used by Hamas for the development of arms, Israel Radio reported. No one was harmed in the attack.
Also Friday night the IAF targeted a minivan belonging to a Hamas operative in northern Gaza City, killing three people and wounding 12, Palestinian hospital officials said.
The IDF said the aircraft struck the vehicle which was carrying weapons and Kassams, causing secondary explosions.
Meanwhile, Palestinians fired mortar shells from the southern Gaza Strip into Israel. The shells fell close to the Gaza security fence; no casualties were reported in the attack.
Separately, Israeli tanks fired five shells near a housing project in the northern Gaza town of Jabalya, slightly wounding five people, according to hospital officials.
IDF officials said the tank fired shells at an open field in northern Gaza after identifying a rocket launch from that area and wanted to prevent further firings.
Palestinian security officials reported that an IAF airstrike targeted an empty Hamas school in northeast Gaza City on Friday night.
Rescue workers said one person was injured. The IDF made no comment.
In another incident, an IDF unit operating in the village north east of Jenin shot and killed an armed Palestinian during clashes, bringing the day's total casualties to nine.
Earlier Friday, Palestinian security officials reported that IAF aircraft had fired two missiles at a Hamas installation in the central Gaza Strip.
There was no word on casualties, and the IDF had no immediate comment. A Hamas spokesman told Hamas TV that he didn't expect any casualties because the group had evacuated key locations likely to be targeted by Israel.
The IDF also struck a Kassam crew that had fired rockets at the western Negev earlier in the day, and killed at least one of its members.
Before dawn Friday, the army hit a building that covered an arms-smuggling tunnel, killing several operatives.
At least 15 Palestinians have been killed since the IDF operation to take over Kassam launch sites began on Thursday, when tanks and infantry joined the air force in hammering away at Hamas targets in the Gaza Strip.
Yaakov Katz and AP contributed to this report.