Here's What Happened in Russia on the First Anniversary of the Killing of Boris Nemtsov

Exactly one year ago, Russian opposition leader and former deputy prime minister Boris Nemtsov was gunned down near the Kremlin in Moscow. Since then, history teacher Nadir Fatov and others have guarded a makeshift memorial at the place where he was killed around the clock, in rain and snow. They have been attacked by pro-Kremlin activists and police have detained them on several occasions, but they keep coming back and replacing the the flowers, candles, and pictures.

In a way, the 20-plus times the memorial has been destroyed mirror the reprisals against Russia's embattled opposition over the past year. Fatov says remembering Nemtsov is vital to the struggle for democratic reform, and he calls his vigil an "indefinite action against political killings in Russia."

On Saturday, Fatov and at least 10,000 others marched through Moscow to commemorate Nemtsov on the anniversary of his death. "The authorities are fighting Boris Nemtsov," Fatov told VICE News at the march. "They want people to forget Boris Nemtsov. But the opposite is happening."

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Although Moscow authorities didn't allow the march route to include Bolshoi Moskvoretsky bridge where Nemstov was murdered, huge lines of people waited to lay flowers at the scene of the crime before and after the march.

Nadir Fatov, one of those who has guarded makeshift memorial where — Alec Luhn (@ASLuhn)February 27, 2016

Demonstrators chanted slogans like "We won't forget, we won't forgive," "Down with the police state," and "Russia will be free," as well as "Putin and Kadyrov are a disgrace to Russia," referring to President Vladimir Putin and his close ally Ramzan Kadyrov, the head of the Chechen Republic.

Zaur Dadayev, the deputy commander of a battalion of Chechen security forces known for its loyalty to Kadyrov, has been charged with killing Nemtsov with four pistol shots to the back, but the suspected mastermind of the crime is still at large. On Saturday, the Nemtsov family's lawyer said Interpol had launched an international search for the suspect, Ruslan Mukhudinov, who reportedly fled from Chechnya to the United Arab Emirates after the murder. Many believe the order to kill Nemtsov came from higher-ranking officials in Chechnya, perhaps even from Kadyrov himself. Putin awarded the Chechen leader a medal just days after the killing.

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In the year since Nemtsov's death, opposition leaders have been harassed, jailed, and assaulted. Others, bizarrely, have had cakes thrown in their faces. Anti-corruption activist Alexei Navalny, a Putin foe whose brother is in prison on embezzlement charges that many view as political, had a cake thrown in his face this week.

Solid turnout for the — Alec Luhn (@ASLuhn)February 27, 2016

Kadyrov, meanwhile, has engaged in increasingly aggressive war of words against liberal opposition figures, decrying them as US agents and "enemies of the people" who should be tried for treason. Kadyrov posted a video earlier this month that showed Nemtsov's fellow Parnas party leader and former prime minister Mikhail Kasyanov in the crosshairs of a sniper rifle, eerily evoking Nemtsov's killing. Days later, a group of men who were reportedly heard speaking Chechen threw a cake in Kasyanov's face in a Moscow restaurant. Pro-Kremlin protesters also threw eggs at him in the city of Vladimir.

Kasyanov later told VICE News that Putin was enabling Kadyrov and others to harass him ahead of the parliamentary elections this fall. "The Kremlin has declared war on me," he said.

A cake to the face is getting off easy compared to moves against other activists and NGOs. This month, a court ordered the human rights group Agora, whose lawyers have represented opposition figures such as Pussy Riot, closed down. In December, opposition activist Ildar Dadin was jailed for three years, a sentence that Amnesty International called a "shocking and cynical attack on freedom of expression."

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In May, Vladimir Kara-Murza, another Parnas party leader who was in the crosshairs video with Kasyanov, was hospitalized after what he suspects was an attempted poisoning. After six months of rehabilitation, he still has to walk with a cane.

Memorial marches for Nemstov were held across Russia on Saturday, and organizers in some cities were harassed and attacked. On Friday, activists in Chelyabinsk said the organizer of the Nemtsov memorial march there, Vyacheslav Kislitsin, had to be hospitalized after he was severely beaten. Kislitsin reportedly said a police officer had been among those who beat him, although police denied this.

At the Nemtsov march in Voronezh, individuals in medical masks threw eggs, green ink, and what appeared to be flour at activists.

Saturday's march in Moscow was largely peaceful, although five members of Putin foe Mikhail Khodorkovsky's Open Russia movement were briefly detained by police. Eight activists were detained in Kemerovo, where authorities refused to allow the march, and three were jailed for 10 days.

Protesters at the Moscow march said they would not to be frightened into silence by the Kremlin or Kadyrov, who has called himself Putin's "foot-soldier." Nemtsov's murder "was so demonstrative, they were trying to intimidate us so much, that I came to say, 'You haven't intimidated us,'" pensioner Tatyana Kulagina said in Moscow.

She carried a sign that read, "Russia will be free, whoever didn't understand will get it," the second half an allusion to a favorite phrase of Kadyrov's.

"After Nemtsov's killing, we have to show that we are not afraid," said photographer Alexander Dmitriyev, who participated in the street protests that Nemtsov helped lead from 2011 to 2013, "and we continue our struggle for democracy and freedom in Russia."

Follow Alec Luhn on Twitter: @ASLuhn