Iranian resistance groups in exile disagree on many issues, but a tragic death this week has brought them together, in disgust and outrage.

The dissident daughter of a another famous Iranian dissident died of a heart attack after being beaten by security forces at her father’s funeral procession, according to those who were there.

Haleh Sahabi, the 54-year-old daughter of Ezatollah Sahabi, died after struggling with plainclothes agents who tried to prevent her from carrying a photo of her father at his funeral procession, witnesses said.

Those witnesses say that when Sahabi then tried to get close to her father’s coffin, she was beaten again, and eventually she suffered a heart attack. Official Iranian sources have tried to blame Haleh Sahabi’s death on the emotional drain of her father’s passing away. They do not connect the numerous beatings she received at his funeral to her heart attack, nor do they even mention those attacks.

The U.S. has spoken out against the violence.

"We condemn the killing of Iranian activist Haleh Sahabi in the strongest possible terms," Mark Toner said in a statement issued on behalf of the U.S. State Department. "Eyewitness and reliable accounts ... are making it clear that Ms. Sahabi died as a result of reprehensible actions taken by Iranian security forces. ...

"It is unfathomable that a government would be so terrified of its citizens that it would order the use of force against a daughter mourning at her father’s funeral," he said. "Indeed, this is a government that regularly brutalizes its citizens, imprisoning them under questionable charges, torturing them, cutting them off from the rest of the world, and denying their fundamental human rights."

The State Department is urging the U.N. Human Rights Council to investigate the incident, he said.

Hadi Ghaemi of the International Campaign for Human Rights in Iran said, “The shameful actions of government thugs in this incident reveal a deep contempt for traditions that belong to all Iranians, and they have resulted in a tragedy. ... The grotesque interference in Ezatollah Sahabi’s funeral is emblematic of the severe repression of Iranian political and civil society activists, who even at their loved ones’ funerals, have to suffer systematic abuse by unaccountable, unidentified individuals.”

Haleh Sahabi, a mother of two, had been let out of jail because her father was about to die. She had been sentenced to two years in August 2009 for political activities. She was a religious woman, who had worked on women’s issues, as well as general humanitarian causes.

Her father was one of the leaders of the Nationalist-Religious Coalition, or NRC, formed after the 1979 American hostage-taking in Iran, by those revolutionaries who opposed the siege of the United States Embassy in Tehran. The NRC became part of the Iranian opposition.

“Irrespective of any political differences that anyone may have with the views and policies advocated by Mr. Sahabi, (a ‘religious nationalist’), the assault and subsequent murder of his daughter during their family’s hour of grief is an unacceptable reminder of the disposition and true nature of an insensitive and brutal regime that has violated our nation and our people over the last 32 years,” former Iranian diplomat Mehrdad Khonsari said.

Jailed human rights lawyer Nasrin Sotoudeh is a young supporter of the NRC. Her court appearance this week was one of the most talked about news items on the popular Iran website, Balatarin.

To many in the Iranian blogosphere, these pictures of Sotoudeh, handcuffed -- as she was briefly reunited with her husband and trying to embrace him with shackled arms as prison guards look on -- make a mockery of a system that established itself in Iran three decades ago, ostensibly in defense of ordinary people.

The pictures of Sotoudeh are being passed around by her supporters, an apparent move to contrast the humanity of this couple, who appear genuinely in love, with the inhumanity of the regime.

"We possess hope because of you," said one person commenting on an Iranian website.

Nasrin just celebrated her 47th birthday and has two young children at home. She was one of the few remaining human rights lawyers left in Iran after the 2009 upheavals.

Mohammad Mostafaei had been defending Sakineh Mohammadi Ashtiani, the woman who had been sentenced to stoning, but whose fate to this day remains unclear. The situation became too difficult for Mostafaei and his family. Iranian authorities were trying to prove he was receiving illicit funds, and that he was making a profit off his human rights work, charges he denies. He escaped Iran via Turkey last year. His family has since joined him. They currently live in exile in Norway.

Houtan Kian took over Ashtiani’s case. He was repeatedly harassed, and eventually he was put in jail and recently handed out a lengthy prison sentence.

Nasrin Sotoudeh is also from a religious family. She received a Masters in International Law from Shahid Beheshti University and has been a prolific writer and activist ever since.

One of the high profile movements she was involved in was the Campaign for One Million Signatures, which was fighting to get the legal inequalities of women overturned in Iranian law. Many women, including Sotoudeh briefly, were arrested during that campaign, which began a few years ago. She ended up defending them all, a fact which encouraged many tentative women to join the fight. Knowing they had Sotoudeh in their corner was a motivator.

But eventually she was silenced, arrested again last September for numerous charges including “propaganda against the state” and thrown in to Evin Prison. She reportedly has been largely denied family visits and is kept in solitary confinement. Sotoudeh has been on hunger strikes. Her sentence is 11 years. For 20 years thereafter, she is also prohibited from practicing law.

Outrage builds over the impunity of the system in these stories about brave Iranian women.

Khonsari said, “It is my hope that every one of my friends will voice their objections to this horrific incident (the beathing of Haleh Sahabi) and help give proper resonance to this beastly act that needs to be brought to the attention of the international community—not just to prove what we all have been saying all these years but to make sure that the criminal perpetrators of this terrible deed are brought to justice.”

Amy Kellogg currently serves as a Senior Foreign Affairs Correspondent based in Milan, Italy. She joined Fox News Channel (FNC) in 1999 as a Moscow-based correspondent. Follow her on Twitter: @amykelloggfox