About 7,500 people are taking part in a march in Moscow on Saturday in commemoration of opposition politician Boris Nemtsov, who was killed a year ago, the Moscow city police department told Interfax.

"Taking part in the procession are 7,500 people," it said.

The demonstration is passing without incidents, the police department said. "Public order is being maintained fully," it said.

Meanwhile, the march organizers have estimated the number of its participants at 100,000. "I think about 100,000 people are taking part in the procession," opposition activist Vladimir Milov told Interfax.

An Interfax correspondent reported from the scene that the marchers have stretched from Rozhdestvensky Boulevard to the end of Petrovsky Boulevard. Some of them are demanding that those who put an assassination contract for Nemtsov be brought to justice and are chanting anti-government slogans.