BILIN, West Bank — Clashing narratives over the case of a 36-year-old Palestinian woman who died on Saturday is fast making her a new symbol of the enduring conflict here, with the Israeli military anonymously casting doubt on Palestinian accounts — backed by medical documents — that she died from inhaling tear gas.

The woman’s relatives, village leaders and staff members at the hospital in Ramallah where she was treated said that she was fatally sickened by tear gas fired on Friday by Israeli forces during the weekly protest against Israel’s separation barrier in the Palestinian village of Bilin. Her mother said she and her daughter, Jawaher Abu Rahmah, were watching the protest from a distance when a cloud of tear gas wafted their way, causing her daughter to collapse.

But Israeli military officials, who insisted on anonymity while their investigation was continuing, told various journalists and bloggers that they had never heard of tear gas killing anyone in the open, and raised the possibility that she had some pre-existing ailment that, alone or compounded by the tear gas, caused her death.

The army routinely fires CS tear gas against the protesters to keep them away from the barrier and to disperse stone-throwing youths. The gas is toxic and can be lethal in closed environments but is considered nonlethal in the open air. Israeli military officials said the gas used on Friday was exactly the same as that used every week.

Pro-Israel advocates quickly pounced on the Israeli military official’s anonymous conjectures, accusing the Palestinians of fabricating the story of death from tear gas for propaganda purposes. The Palestinians riposted, saying the Israelis were making an underhanded attempt to discredit them and cover up army actions. The Palestinian government’s media center called the Israeli arguments “reprehensible,” describing them as “half truths,” “misinformation” and “lies.”

Both sides are aware of the potency of such symbols. A brother of Ms. Abu Rahmah, Bassem, became a rallying point for the Bilin protests in 2009, when he died after being struck in the chest by an Israeli tear gas canister. Video of a 12-year-old Palestinian being shot to death in Gaza in 2000 during a gun battle between Israeli forces and Palestinians provided an iconic image that fanned Palestinian rage in the early stages of the second intifada. Israel first apologized for the death of the boy, Muhammad al-Dura, then concluded he had probably been killed by Palestinian fire. Some critics even charged that the whole episode had been staged.

For now, the debate has focused on Ms. Abu Rahmah’s medical history and possible conflicts in hospital records.

She went to work as usual on Thursday, according to her employer in Ramallah. On Friday morning, one of her brothers, Samir, recalled, she was chatting happily about New Year and other subjects with her family at home.

Local Palestinians, bolstered by international and Israeli supporters, have held weekly protests against Israel’s separation barrier in Bilin for the past five years, turning the village into a symbol of Palestinian defiance. Friday’s demonstration was billed as a particularly large one to observe the end of 2010.

Ms. Abu Rahmah’s mother, Soubhiya, said she was with her daughter and several neighbors on a rise near their home at the edge of the village, watching the confrontation between the Israeli forces and activists who were closer to the barrier across the valley.

The mother and others described a “cloud” of tear gas carried toward them on the wind. Witnesses said that Ms. Abu Rahmah soon began vomiting and emitting white foam from her mouth.

Her brother Samir, 34, was at home when neighbors called him for help. He said he found his sister lying on the floor of the neighbor’s house. “She said, ‘I’m going to die,’ ” he recalled, standing outside the family home, a small, weathered structure with a bare concrete floor.

A few minutes later, at 1:20 p.m., an ambulance arrived, according to a case form from the Palestine Red Crescent Society. It delivered Ms. Abu Rahmah to the Palestine Medical Complex in Ramallah and returned to its base by 2:43 p.m., according to the driver, Saher Bisharat.

Another brother, Ahmed, said he stayed all night with Ms. Abu Rahmah in the hospital. He recounted that her situation deteriorated and her heart stopped three times on Saturday morning before she died.
On Saturday night, an Israeli military official said the army had received an initial report from the Palestinians that a woman who was hospitalized after inhaling tear gas had been released and died later at her home. While not disputing that Ms. Abu Rahmah had been affected by tear gas, the official questioned whether she had some pre-existing medical condition that might have contributed to her death, or whether her death could have been a result of medical negligence.

A report dated Jan. 2 from the hospital and signed by two doctors and the director, Dr. Muhammad Aideh, said her death was caused by “unknown gas inhalation” after an “attack by Israeli soldiers as the family said.” Dr. Aideh also said the patient “died from lung failure that was caused by tear gas inhalation, leading to a heart attack.”

On Tuesday, the military official said that records showed that Ms. Abu Rahmah was given a drug at the hospital that can be used to treat leukemia or a drug overdose. The official also suggested that Ms. Abu Rahmah could have had asthma. The military also said that Palestinian medical officials had not immediately provided the military with the medical reports, a lack of cooperation that the military considered problematic.

The hospital report states that Ms. Abu Rahmah had “no history of chronic disease.” Family members said she underwent a CT brain scan in late December after complaining of headaches. A report from the Shafey Diagnostic Center said the scan showed everything to be normal. The family said the problem was an inner ear infection that was subsequently treated and cured.

The military official noted that there were no photographs or video showing Ms. Abu Rahmah at the protest on Friday, but that is not surprising since she was not at the forefront of the demonstration.

The Israeli military’s questions focus chiefly on discrepancies in timekeeping. The military says that according to one medical report, Ms. Abu Rahmah’s laboratory test results were registered at 2:45 p.m. on Friday, whereas another report states that she was admitted at 3:20 p.m.

Her brothers said that 3:20 p.m. was the time when she admitted to the intensive care unit. The tests, they said, were carried out earlier in the emergency room.

The family refused an autopsy on religious grounds. Ms. Abu Rahmah was buried Saturday afternoon in a small cemetery near her home, next to her brother Bassem.