MOSCOW — Thousands of people have marched down a central Moscow boulevard to mark the third anniversary of the slaying of Russian opposition politician Boris Nemtsov.

Nemtsov was shot and killed on Feb. 27, 2015 while walking on a bridge near the Kremlin. His death sent shock waves through Russia's beleaguered opposition.

Demonstrators at the front of Sunday's anniversary event carried a banner reading, "These bullets are in all of us."

Two candidates in Russia's presidential election next month — Ksenia Sobchak and Grigory Yavlinsky — participated in the march.

An officer in the security forces of Chechnya's Kremlin-backed leader Ramzan Kadyrov was convicted of firing the shots that killed Nemtsov and received a 20-year prison term. Four other men convicted of being involved in Nemtsov's slaying received 11 to 19 years.