Casualties increased by three following the latest attack, it said.
The strike hit a house in the west of the Gaza Strip. One of the martyred was a woman and another was a disabled person, an official from the Civil Defense teams told Anadolu Agency.
One of the nine children who were martyred was a 10-year-old girl and the others were boys of various ages, the ministry said.
Meanwhile, many houses and workplaces were either completely destroyed or became unusable due to the attacks.
The Israeli army announced the launch of Operation Guardian of the Walls late on Monday against the Gaza Strip.
It also announced that an air attack had been carried out on the Gaza Strip, from which many rockets have been fired into southern Israel.
Tensions have been running high in the Sheikh Jarrah neighborhood of occupied East Jerusalem since last week, when Israeli settlers swarmed in after an Israeli court ordered the eviction of Palestinian families.
Palestinians protesting in solidarity with the residents of Sheikh Jarrah have been targeted by Israeli forces.
Israel occupied East Jerusalem during the 1967 Arab-Israeli war and annexed the entire city in 1980 -- a move that has never been recognized by the international community.