Lyudmila Alekseyeva, a veteran defender of human rights and a prominent Russian opposition figure, has died in Moscow. She was 91.

"She remained a human rights activist until the last moments. She really lived her life for her friends. This is a terrible loss for the entire human rights community," Mikhail Fedotov, head of the Russian presidential council of human rights, said in a statement.

No cause of death was given, but the council said she had been treated several times in Moscow’s City Clinical Hospital No. 15 for unspecified ailments.

"This was not the first time she came to this hospital. Doctors have repeatedly saved her in the most difficult situations, but there are situations where doctors are powerless. That is exactly what happened today," the council said in the statement.

Once described by The Moscow Times as "the matriarch of Russia's human rights community," Alekseyeva had been involved in rights campaigning since the 1960s.

An archaeologist by training, she quickly grew disillusioned by the Soviet Union and abandoned what had started as a promising academic career.

She campaigned for dissidents who had run afoul of Soviet authorities, including writers Andrei Siniavsky and Yuli Daniel, sentenced to prison for criticizing Soviet authorities in the foreign press.

She also clandestinely worked as a typist for the Chronicle Of Current Events, the leading "samizdat" underground publication detailing human rights violations in the U.S.S.R.

In an interview with RFE/RL's Russian Service in May 2016, Alekseyeva recalled how fellow dissident Yury Orlov first came up with the idea to establish the Moscow Helsinki Group.

"In early May 1976, he called me and asked, 'Lyuda, the weather is beautiful, would you like to go for a walk in downtown Moscow?'" she said. "We were on friendly terms, but we usually met only for work. I understood that he was inviting me to talk outside, since our homes were bugged."

The pair met and Orlov laid out his plan to establish an organization that would monitor the Soviet Union's compliance with the principles enshrined in the Helsinki Accords.

The accords were signed in August 1975 by the Soviet Union, the United States, Canada, and all European countries except Albania, which became a signatory in 1991 -- 35 states in total.

The goal was to reduce tensions between the communist bloc and the West and uphold respect for fundamental freedoms.

Alekseyeva immediately backed Orlov's proposition.

Days later, on May 12, 1976, the Moscow Helsinki Group was created, with Orlov, Alekseyeva, and a dozen other prominent dissidents as founding members.

Soviet authorities immediately retaliated. Alekseyeva says only three of the group's founders, including herself, evaded arrest.

"For many, she was and will remain the soul of the human rights movement, an example we should try to be worthy of," an obituary posted on the Moscow Helsinki Group official site says.

She eventually fled to the United States with her family in 1977, where she continued advocating for human rights and took up freelance work for RFE/RL and Voice of America.

In 1985, she published her first book, Soviet Dissent, devoted to the history of the dissident movement. She followed that in 1990 by issuing Thaw Generation, an autobiography co-authored by Paul Goldberg.

The Soviet Union collapsed the following year, and in 1993, after 16 years in exile, Alekseyeva and her husband were finally able to return home.

She returned to being a leading figure of the human rights movement, tirelessly denouncing rights abuses under former President Boris Yeltsin.

Most recently, Alekseyeva's target had been the soft authoritarian regime introduced by President Vladimir Putin and his all-powerful ruling party, United Russia.

Her frail frame hid an unwavering resolve as she led demonstrations and gave conferences around the world to press for freedoms and human rights in Russia.

She was a talented orator and was often called upon to address demonstrators at rallies, such as one in Moscow in March 2011.

"We are not the ones who decide who will lead the country. It is those who are in power who decide, and of course they make decisions based on their own interests. This regime put in place by United Russia has shown that it does not take our interests into account," she said.

Kremlin spokesman Dmitry Peskov late on December 8 told the Interfax news agency that Putin "appreciates Lyudmila Alekseyeva's contribution to the development of civil society in Russia."



He added that Putin respected her positions on many issues and that the president had sent a letter of condolences to her family.



Alekseyeva’s crusade for human rights elicited international praise and accolades, including the Sakharov Prize and a nomination for the Nobel Peace Prize.

But it also earned her enemies.

In 2006, Russian authorities accused her of involvement with British intelligence. She was vilified by pro-Kremlin youth groups, who branded her a Nazi and one of the nation's greatest foes.

In March 2010, she was assaulted at a Moscow subway station while paying her respects to the victims of a bombing attack there a few days earlier.

Alekseyeva, already walking with difficulty, was famously detained on December 31, 2009, for leading an unsanctioned New Year’s Eve protest dressed up as Snow Maiden.

Her arrest sparked outrage in Russia and beyond, with top U.S. and European Union officials penning strongly worded disapprovals.

She vigorously denounced rampant abuse against civilians in war-ravaged Chechnya and, later, the killing of investigative journalist Anna Politkovskaya and rights campaigner Natalya Estemirova.

Both women had actively worked to uncover atrocities committed against the local population by pro-Moscow law enforcement officials and separatist rebels.

Alekseyeva blamed both the Kremlin and its handpicked leader in Chechnya, Ramzan Kadyrov, for the killings of activists battling rights violations in the North Caucasus.

"It is the duty of Ramzan Kadyrov, as president of Chechnya, to create conditions there that prevent such killings from taking place. He has failed to do that. This is why he is guilty, regardless of who killed these people and why," she said.

Alekseyeva took a strong stand against a raft of Kremlin initiatives, including the mass deportations of Georgian citizens in 2006 and the introduction of harsh new restrictions on nongovernmental organizations operating in Russia.

When anticorruption lawyer Sergei Magnitsky died in pretrial detention in 2009, she actively lobbied for a probe into his death.

Her activism deepened after she quit the president's human rights council in June 2012, citing interference from the Kremlin.

She spent her remaining years doing what she had done for the best of her life: warning against the rollback on human rights and democratic freedoms in Russia.

"A serious onslaught is being waged on all the rights of citizens -- on their voting rights, on their right to expression, as well as on their right to unite. All of these rights are guaranteed by our constitution, but our authorities have long forgotten about its existence," she said.

Despite her acerbic attacks against the Kremlin, the reverence she inspired shielded her from serious trouble with authorities.

Putin even made sure to congratulate her on her 90th birthday and even granted her a state award for human rights in December 2017.

But Alekseyeva, who had been an activist for more than three decades when Putin was first elected in 2000, already had become deeply disillusioned with his leadership during his first two terms as president.

In an interview in 2012, shortly after Putin returned to the presidency following a four-year stint as prime minister, Alekseyeva told Reuters that when she first met Putin in 2002, she was impressed by his humility and willingness to listen to activists like herself.

But when they met again in 2006, Putin was "a different man," who had come "to believe that everyone wants him to stay in power," she said.

"He doesn't understand. It's a terrible thing to have power.... Very few people can handle it properly," she added.

Alekseyeva leaves behind two sons, Sergei and Mikhail.