Nearly every Friday for the past five years, Jawahar Abu Rahmah, 36, was a regular face at the weekly protests in her village of Bil'in.
In her red-checked headscarf, she marched with hundreds of other activists on the Israeli-built barrier that has separated farmers from large tracts of their land. The snaking fence of barbed wire and towering slabs of concrete, projected to stretch 723km when completed, has disrupted the lives of thousands of Palestinians.
Even after her brother, Bassem, was killed when an Israeli tear-gas canister struck his chest at a demonstration there in 2009, those who knew her say Jawahar, one of seven in her family, remained committed to the non-violent ethos of the Bil'in demonstrations.
Last Friday she became ill during the weekly protest. The following day she died from what doctors at a hospital in Ramallah said was tear-gas asphyxiation.
The young woman's death prompted an immediate response from Saeb Erekat, the chief Palestinian negotiator in peace talks with Israel, who condemned it as "this abominable crime by the Israeli occupation army in Bil'in against people taking part in a peaceful demonstration".
Mr Erekat is not the only one to be concerned. Jawahar's death has raised questions about what critics say are the Israeli military's excessive, and sometimes deadly, methods of dealing with demonstrators in the West Bank.
For one thing, she was not directly participating in the protest. According to family and friends, she was watching from near her family home tens of metres away. She became ill, they say, when gusts of wind swept a thick plume of tear gas in her direction.
The Abu Rahma family lawyer, Michael Sfard, an Israeli citizen, accused the military of covering up its use of large amounts of gas during the protest.
The military announced on Saturday that it would launch an investigation, but Mr Sfard said: "Once again the army is covering up the actions of its men, instead of apologising and conducting a serious inquiry."
Israel's military called Friday's gathering a "violent and illegal riot" that forced it to disperse the crowd. While striving to avoid violence, protest organisers in the West Bank have struggled to prevent young people from throwing stones - behaviour that, as on Friday, provokes what protesters say is a disproportionately violent response from soldiers, involving barrages of tear gas and rubber bullets.
Iyad Haddad, a West Bank field researcher for the Israeli human-rights group B'Tselem, said he believed the gas could have exacerbated an illness from which Jawahar was already suffering, and which could have been the reason she did not take part in the protest.
"Her brother told me a week before the incident that she had become sick and had to see a specialist," he said.
Jawahar's family said that because many of the Bil'in protesters regularly inhale tear gas, they had trouble believing that this alone could have killed her.
Her younger brother Ashraf, 29, said that when he learnt that she had been taken to hospital after inhaling the tear gas, he was not surprised.
"I thought it was normal," he said, sitting on one of the plastic chairs in front of the family home yesterday as he received condolences from neighbours and friends.
"All the time, people here have to go to hospital because of tear gas, and usually they come out fine. That's why I didn't think she was in a bad state."
When he heard the news of her death, he said, "I had to sit, alone, and just think. You go crazy if you think about why she died, what could have caused this."
Ashraf and his brother Ahmed, 37, described their sister as the one who kept their family together for years.
In the sixth grade, Jawahar left school to tend to her brothers and sisters. Her father, a construction worker, became ill, and her mother looked to her for support.
"She was both our sister and our mother," Ahmed said. "She was the one you went to if you had a problem. She was the pillar of our family."
She never married and had several jobs. With the help of her income, the family said, construction began on a new house for their brother, Bassem.
Work on the house halted when he died, and the brothers - lacking gainful employment - now wonder if it will ever be finished.
"I don't know what we'll do without her," Ahmed said.