Thousands of Russians descended on polling stations across Russia on Sunday, the last day of a three-day presidential election, in what anti-Kremlin activists said was a protest against the reelection of President Vladimir Putin.

Putin is poised to extend his nearly quarter-century rule for six more years. He would become Russia's longest-serving leader for more than 200 years by the end of his term, according to Reuters.

The election has been deemed not 'free or fair,' by the EU and NATO, due to the Kremlin's efforts in tamping down opposition.

Putin is facing off against three Kremlin-approved candidates representing political parties loyal to him and his policies.

The vote comes just over two years after Putin ordered the invasion of Ukraine. It is illegal in Russia to call it a war or show dissent to the operation. 

The election is taking place amid attacks within Russia by Ukrainian missiles and drones, according to the Associated Press. Those strikes have killed several people.

One Moscow voter, who identified himself only by his first name, Vadim, told the AP that he hoped to see change, but said that "unfortunately, it's unlikely." 

Another, Yulia, said that she was voting for the first time.

"Even if my vote doesn't change anything, my conscience will be clear...for the future that I want to see for our country," she said.

The vote also comes in the shadow of the recent death of Putin foe Alexei Navalny in an Arctic prison.

Navalny's associates urged those unhappy with Putin or the war to protest by coming to the polls at noon Sunday. Navalny reportedly showed support for the protest shortly before his death.

Ivan Zhdanov, the head of Navalny's Anti-Corruption Foundation, said that the opposition's call to protest had been successful.

"The action has shown that there's another Russia, there are people who stand against Putin," he told the Associated Press.