The demonstrators included African students, members of the pro-government youth group Nashi, and self-declared anarchists.
The head of the local African Unity movement (Aliu Tunkara) said the demonstrators asked for a meeting with the city governor.
The Cameroonian was killed and a second person from Africa was injured in an assault near a dormitory in St. Petersburg on the evening of 24 December.
Police are investigating whether the attack was motivated by the victims’ race. Racist attacks have been on the rise in Russia, including in St. Petersburg, where a Congolese student was murdered in September.
A Peruvian student was killed in the city of Voronezh in October.