Thousands of people are protesting in the Siberian city of Kemerovo, angry at Russian officials over the leisure complex fire that killed at least 64 people, 41 of them children.
President Vladimir Putin arrived in Kemerovo earlier and blamed "criminal negligence" for Sunday's blaze.
Relatives say as many as 85 people are still missing, most of them children, according to Interfax news agency.
Investigators say the fire alarm was switched off and exits were blocked.
Several thousand people rallied outside the local government headquarters on Tuesday, demanding that officials be sacked over the fire safety shortcomings.
There were also some chants of "Putin resign!"
Kemerovo residents' anger has built up since Sunday and it burst forth at the rally of several thousand outside the city administration building.
The main slogans were "Truth!" and "Resign!" - directed at local officials.
The most active among them was Igor Vostrikov, whose wife, sister and three children - aged two, five and seven - all died in the fire.
Deputy governor Sergei Tsivilev accused him of trying to gain publicity out of the tragedy. Igor's reply was that his entire family had suffocated in the cinema, unable to escape because the doors were locked.
Fighting back tears, he described his wife's last moments, when she phoned him, short of breath. "There was no panic - she was saying goodbye."
"I have nothing more to lose," he said.
Thousands of Russians Take to the Streets Demanding Putin to Resign
Logan Bailey
Dylan Roberts
lmao kike false flags getting more and more desperate
Isaiah Jones
proof?
Austin Rivera
...
Josiah Bailey
can you name a state leader no-one ever demanded to step down?
Aaron Ramirez
the absolute state of kiketv
Julian Johnson
What about all the fires in America that kill children? Where is the outrage?
Robert Bennett
Yes I do
Jason Cooper
they're not dying in a mall fire that killed mostly children
Benjamin Gomez
another false flag, like vegas, except they didn't botch it