The U.N. human rights office on Wednesday accused Israeli forces of repeatedly violating fundamental principles of the laws of war in their military campaign on Gaza.

In a report assessing six Israeli attacks that caused a high number of casualties and destruction of civilian infrastructure, the U.N. human rights office (OHCHR) said Israeli forces "may have systematically violated the principles of distinction, proportionality, and precautions in attack."

"The requirement to select means and methods of warfare that avoid or at the very least minimise to every extent civilian harm appears to have been consistently violated in Israel's bombing campaign," said U.N. High Commissioner for Human Rights Volker Türk said Wednesday.

Israel's permanent mission to the United Nations in Geneva characterized the analysis as "factually, legally, and methodologically flawed."

"Since the OHCHR has, at best, a partial factual picture, any attempt to reach legal conclusions is inherently flawed," the Israeli diplomatic mission said.

The report details six incidents that took place between Oct. 7 and Dec. 2, in which the U.N. human rights office was able to assess the kinds of weapons, the means and the methods used in these attacks.

"We felt that it was important to get this report out now, especially because in the case of some of these attacks, some eight months have passed, and we are yet to see credible and transparent investigations," said Ravina Shamdasani, spokesperson for the OHCHR.

"We call first on the Israeli authorities to take steps to ensure that proper investigations, transparent investigations are held."

She added that, in the absence of transparent investigations, there would be "a need for international action in this regard as well."

Serious concerns

The U.N. report also raised concerns over Israel's repeated use of heavy bombs in the densely populated Gaza Strip.

It provided details on the six attacks, which it said were emblematic of a concerning pattern, involving the suspected use of up to 2,000-pound bombs on residential buildings, a school, refugee camps and a market

The rights office said it had verified 218 deaths in those attacks, but said it had information indicating the number of fatalities "could be much higher".

Among the attacks listed were the strikes on Ash Shujaiyeh neighbourhood, in Gaza City on Dec. 2 last year.

It caused destruction across an approximate diagonal span of 130 meters, destroying 15 buildings and damaging at least 14 others, it said.

The extent of the damage and the craters visible and seen on satellite imagery indicated that around nine 2,000-pound GBU-31 bombs were used, it said, adding that it had received information that at least 60 people were killed.

GBU-31s, along with 1,000-pound GBU-32s and 250-pound GBU-39s "are mostly used to penetrate through several floors of concrete and can completely collapse tall structures," U.N. rights office spokesperson Jeremy Laurence told reporters.

The deadliest war on Gaza was triggered by the Oct. 7 Hamas incursion of Israel, which resulted in the deaths of 1,194 people, according to an AFP tally based on Israeli official figures.

The resistance groups also seized 251 hostages. Of these, 116 remain in Gaza, although the army says 41 are dead.

Israel's genocidal war in response has since killed more than 37,400 people in the Palestinian territory, according to health authorities there.

Last week the U.N. human rights office said the killing of civilians during an Israeli operation to free four hostages could amount to war crimes.