Ninety percent of casualties brought to Gaza's main hospital during Israel's winter offensive against Hamas were civilians, according to a new book by one of Norway's most famous and controversial physicians, Dr. Mads Gilbert.

The book, scheduled to be published this month under the title "I in Gaza," recounts Gilbert's experiences as a volunteer at Shifa Hospital in Gaza City and focuses on individual stories by patients and medical staff.

The 318-page account surveys events "which in themselves call people to politically mobilize," said Gilbert, who is also known for his vocal criticism of Israel, in a phone interview with Haaretz last week.

Gilbert's pro-Israel critics downplay the book's potential impact, citing his "political motivation" and "unreliability," and pointing out his communist affiliations and statements after the September 11, 2001, attacks apparently in support of terrorism against the United States.

"Among the patients killed and injured at Shifa Hospital, Gaza's largest medical facility, 80 to 90 percent we saw were civilians," said Gilbert, a frequent visitor to Gaza and the West Bank. He arrived at Shifa last winter with his colleague, Dr. Erik Fosse, on the fourth day of fighting, December 31, through the Rafah border crossing.

Asked how he was able to tell combatants apart from civilians, Gilbert - who does not speak Arabic - said: "We are not naive, we asked the patients who could talk [through a translator] where they had been at the time of the injury and what they were doing. We know a fighter can also look like a civilian. I've been working there for past 20 years."

Gilbert and Fosse are both members of the Norwegian Aid Committee (NORWAC), which describes itself as "a humanitarian organization that works mainly with health care issues," and which focuses on aid to Palestinians.

"We didn't have the opportunity to do scientific assessment of the overall number of people killed and injured but overall assessments shows that 1,400 people died in Gaza, 80 to 90 percent of them civilians, more than 300 children were killed and more than 1,600 injured " Gilbert, 62, said.

But the Israel Defence Forces says that about 1,100 Palestinians were killed during the offensive, the vast majority of whom were militants.

According to Gilbert, throughout his 10-day stay in January, he hardly left the hospital, which was not bombed.

"Did the Israeli army bomb Hamas when it bombed UN shelters for children?" Gilbert demanded in response to a question about his feelings toward Hamas' attacks against Israeli civilians.

Though very critical of Israel - which he accuses of a "moral disaster" - Gilbert appears to have a more tolerant view of Hamas. "We do no support Hamas or Fatah, but we have been working with the organization that the Palestinians chose for leaders," he said when asked about the level of his cooperation with Hamas.

"If I needed to treat wounded people in Israel I would not refuse because of [Foreign Minister] Avigdor Lieberman," he added.

According to the IDF, Hamas' leader in Gaza, Ismail Haniyeh, operated a command center inside Shifa Hospital throughout the three-week offensive. But Gilbert says he saw no indication of this. "With our eyes we saw nothing to substantiate the claim, but we are not journalists or investigators," he told Haaretz.

Professor Gerald Steinberg, founder of the Jerusalem-based organization NGO Monitor for review of non-governmental bodies, says Gilbert's account is "untrustworthy" because of his "one-sided and politically-motivated view."

"By justifying terror, supporting Hamas and fueling the conflict, NORWAC and Mads Gilbert have violated the Hippocratic Oath - 'first, do not harm,'" Steinbeg says.

Israeli government spokesperson Mark Regev, meanwhile, says Gilbert has a history of "unreliable and political" reports to foreign media.

Although he says the book is a "factual account," Gilbert concedes that he is committed to politically supporting the Palestinians. "We are not neutral. We chose medical work in Gaza, not Sderot," he said. The first "medical mission in support of the Palestinians" that Gilbert went on was in 1981 to Beirut, around the time of the first Lebanon War.

Gilbert, a former activist in Norway's Red Party, is prepared to call Hamas a terrorist entity "only if this applies to Israel as well," as "both obtain political and military goals by creating terror in civilians."

"We have had enough yellow stars and the label of "terrorist" being applied indiscriminately to justify killing," added the Norwegian physician, who is quoted by his local media as having compared Gaza to the Warsaw Ghetto.

But when asked about the comparison, Gilbert nonetheless said he does not view Israel's actions as comparable to the Nazi genocides. "What Israel is doing is terrible enough without that comparison," he argued.

In 2001, Gilbert told a Norwegian paper that "under certain conditions" he "might understand 9/11." During the interview with Haaretz, he said that he made the statement "just to start the discussion" but has since retracted the statement. "I should never have said it. I don't support any attack on any civilians," he clarified.

However, in the 2001 interview with the Norwegian paper Dagbladet, Gilbert was asked whether he realized that his support for terrorist attacks on U.S. civilians would generate angry reactions. "Yes, this can only be expected. The white world cannot comprehend that such an act [9/11] can be viewed from another perspective," he is quoted as saying.