A majority of Palestinians killed in dozens of Israeli attacks on Gaza homes in the 2014 war with Hamas were women, minors or elderly people, and some of the strikes violated the rules of war, an Israeli rights group said Wednesday.

The B'Tselem group called strikes on homes "one of the appalling hallmarks of the fighting" and said they were part of a policy approved at the top levels of the government and the military.

"There is no question in our minds that this is not the outcome of a low-level decision, but rather a matter of policy, a policy that in some cases has violated international humanitarian law, in other cases raises severe questions" about legality of the policy, said the group's director, Hagai El-Ad. "So far, there have not been explanations, convincing explanations, by the government of the state of Israel."

Israeli government officials referred requests for comment to the Israeli military which had no immediate response. The military has said in the past it complied with the rules of combat in the attacks on houses.

Israel fought the war to halt rocket fire from Gaza.

During the fighting, Israel launched about 5,000 airstrikes and unleashed thousands of artillery at Gaza, while Gaza militants fired about 4,300 rockets and mortar rounds at Israel. More than 2,200 Palestinians were killed, most of them civilians, according to U.N. figures. Sixty-seven soldiers and five civilians were killed on the Israeli side.

As part of the fighting, Israel attacked dozens of Gaza homes, claiming they were being used as military command centers or for storing weapons. In most cases, the military refused to say exactly who or what was targeted.

B'Tselem looked at 70 strikes in which at least three people at been killed — a portion of the overall total of attacks. More than 70 percent of 606 Palestinians killed in these 70 strikes were minors, women and older men, the group said.

Another Israeli group, NGO Monitor, said the count was skewed by underreporting deaths of combatants.

International law experts say even a high civilian death toll does not, on its own, constitute evidence of war crimes, and that each case has to be examined separately.

Under the rules of warfare, homes can be attacked if they are used for military purposes. Civilian deaths must be proportionate to the military advantage gained from an attack, but there is no precise formula.

B'Tselem said Israel adopted an overly broad interpretation of what may be considered a military target and subverted the principle of proportionality, resulting in an unlawful policy.