Kremlin officials and Russia's opposition have gathered to pay tribute to prominent human rights activist Lyudmila Alexeyeva, who died over the weekend.

Alexeyeva, a staunch and uncompromising rights advocate, died in Moscow on Saturday at the age of 91. She made a name for herself in the 1960s and '70s protesting the treatment of Soviet political prisoners. She returned to Russia in 1993 after spending more than two decades in exile, and continued to be an energetic champion for human rights.

Friends, family as well as political figures including President Vladimir Putin and opposition leader Alexei Navalny on Tuesday came to pay their respects to a community center in central Moscow where the wake was held.

Russian President Vladimir Putin, left, speaks to Lyudmila Alexeyeva's son Professor of Economics at Indiana University, Mikhail Alekseev, he comes to pays his last respects to Lyudmila Alexeyeva, the Moscow Helsinki Group Chair and human rights activist during a farewell ceremony in Moscow, Russia, Tuesday, Dec. 11, 2018. A Russian rights official says Lyudmila Alexeyeva, who was forced into exile by Soviet authorities after founding Russia's oldest human rights organization in 1976, has died in a Moscow hospital at 91 it was reported on Saturday, Dec. 8, 2018. (Alexei Druzhinin, Sputnik, Kremlin Pool Photo via AP)

Russian President Vladimir Putin, left, speaks to Lyudmila Alexeyeva's son Professor of Economics at Indiana University, Mikhail Alekseev, he comes to pays his last respects to Lyudmila Alexeyeva, the Moscow Helsinki Group Chair and human rights activist during a farewell ceremony in Moscow, Russia, Tuesday, Dec. 11, 2018. A Russian rights official says Lyudmila Alexeyeva, who was forced into exile by Soviet authorities after founding Russia's oldest human rights organization in 1976, has died in a Moscow hospital at 91 it was reported on Saturday, Dec. 8, 2018. (Alexei Druzhinin, Sputnik, Kremlin Pool Photo via AP)

Russian President Vladimir Putin, left, pays his last respects to Lyudmila Alexeyeva, the Moscow Helsinki Group Chair and human rights activist during a farewell ceremony in Moscow, Russia, Tuesday, Dec. 11, 2018. A Russian rights official says Lyudmila Alexeyeva, who was forced into exile by Soviet authorities after founding Russia's oldest human rights organization in 1976, has died in a Moscow hospital at 91 it was reported on Saturday, Dec. 8, 2018. (Alexander NemenovPool Photo via AP)

Russian President Vladimir Putin, left, pays his last respects to Lyudmila Alexeyeva, the Moscow Helsinki Group Chair and human rights activist during a farewell ceremony in Moscow, Russia, Tuesday, Dec. 11, 2018. A Russian rights official says Lyudmila Alexeyeva, who was forced into exile by Soviet authorities after founding Russia's oldest human rights organization in 1976, has died in a Moscow hospital at 91 it was reported on Saturday, Dec. 8, 2018. (Alexander NemenovPool Photo via AP)

Russian President Vladimir Putin, left, pays his last respects to Lyudmila Alexeyeva, the Moscow Helsinki Group Chair and human rights activist during a farewell ceremony in Moscow, Russia, Tuesday, Dec. 11, 2018. A Russian rights official says Lyudmila Alexeyeva, who was forced into exile by Soviet authorities after founding Russia's oldest human rights organization in 1976, has died in a Moscow hospital at 91 it was reported on Saturday, Dec. 8, 2018. (Alexander NemenovPool Photo via AP)

Russian President Vladimir Putin, left, pays his last respects to Lyudmila Alexeyeva, the Moscow Helsinki Group Chair and human rights activist during a farewell ceremony in Moscow, Russia, Tuesday, Dec. 11, 2018. A Russian rights official says Lyudmila Alexeyeva, who was forced into exile by Soviet authorities after founding Russia's oldest human rights organization in 1976, has died in a Moscow hospital at 91 it was reported on Saturday, Dec. 8, 2018. (Alexander NemenovPool Photo via AP)

Russian President Vladimir Putin, left, pays his last respects to Lyudmila Alexeyeva, the Moscow Helsinki Group Chair and human rights activist during a farewell ceremony in Moscow, Russia, Tuesday, Dec. 11, 2018. A Russian rights official says Lyudmila Alexeyeva, who was forced into exile by Soviet authorities after founding Russia's oldest human rights organization in 1976, has died in a Moscow hospital at 91 it was reported on Saturday, Dec. 8, 2018. (Alexei Druzhinin, Sputnik, Kremlin Pool Photo via AP)

Russian President Vladimir Putin, left, pays his last respects to Lyudmila Alexeyeva, the Moscow Helsinki Group Chair and human rights activist during a farewell ceremony in Moscow, Russia, Tuesday, Dec. 11, 2018. A Russian rights official says Lyudmila Alexeyeva, who was forced into exile by Soviet authorities after founding Russia's oldest human rights organization in 1976, has died in a Moscow hospital at 91 it was reported on Saturday, Dec. 8, 2018. (Alexei Druzhinin, Sputnik, Kremlin Pool Photo via AP)