Medics and the interior ministry of the Hamas-run Gaza Strip said an Israeli air strike killed a senior police official and eight other officers when it hit their vehicle near the entrance to Zawayda town in the enclave's centre.
At least 14 other people, mostly bystanders, were wounded, the Gazan health ministry said.
Earlier on Sunday, health officials said an Israeli air strike had killed three people - a man, his pregnant wife and their son - in the western area of Nuseirat in the central Gaza Strip.
In the Israeli-occupied West Bank, a Palestinian father, mother and two of their children were killed as they drove in the occupied West Bank, Palestinian health authorities said, and the Israeli military said the incident was under review.
In the Gaza Strip there have been regular outbreaks of violence since a ceasefire went into effect in October following two years of devastating war triggered by Hamas-led attacks in Israel on October 7, 2023.
While Israeli attacks in the strip declined in the days after the US and Israel launched attacks on Iran on February 28, according to residents, medics and analysts, they have since begun to rise again.
Israeli fire has killed at least 36 Palestinians since the outbreak of the Iran war, Gazan health officials say.
The territory's health ministry says that at least 670 people have been killed by Israeli fire since the October ceasefire.
Israel said four soldiers were killed by Gaza Strip militants over the same period.
In the West Bank village of Tammun, Palestinian health authorities said Ali Khaled Bani Odeh, 37, his 35-year-old wife Waad and two of their sons aged five and seven died after being shot in the head while two of their other children sustained injuries.
The Israeli military said in a statement that forces had operated in the village of Tammun to arrest Palestinians wanted for involvement in "terrorist" activity against security forces.
"During the operation, a vehicle accelerated toward the forces, who perceived an immediate threat to their safety and responded with gunfire. As a result, four Palestinians who were in the vehicle were killed," the military said.
The circumstances of the incident were under review, it said.
Speaking to Reuters at the hospital, Khaled, 12, one of the two surviving boys, said he heard his mother crying and his father praying before shots sprayed the car.
"We came under direct fire, we didn't know the source. Everyone in the car was martyred, except my brother Mustafa and me," the boy said.
He said soldiers had pulled him out of the vehicle before beating him and cried: "We killed dogs."
The Palestinian health ministry said one Palestinian was also killed in an attack by Israeli settlers overnight.
Rights groups and medics have accused Israeli settlers in the West Bank are taking advantage of curbs on movement imposed during the US-Israeli war on Iran to attack Palestinians, with military roadblocks preventing ambulances from reaching victims quickly.
Settlers have killed at least five Palestinians in the West Bank since the Iran war began on February 28, according to the Palestinian health ministry.
