A teenage gunman shot dead at least 20 people and injured 40 more before killing himself at a technical college where he was a student in Russian-annexed Crimea.
Grieving residents laid flowers and lit candles in the Crimean port city of Kerch on Thursday, a day after an armed teenager went on a shooting rampage at his college, killing 21 people, most of them fellow pupils.
The suspected attacker was found dead from a self-inflicted gunshot wound after an attack that saw dozens injured and a bomb set off in the college canteen in the Black Sea region, law enforcement officials said.
Stunned residents gathered on Thursday to mark a three-day official mourning period declared in the region.
Orthodox priests sang prayers in the street, leading a memorial service near the college.
"Where were the guards?" a tearful woman at a memorial asked. "Where were the men who were there in large numbers? Why was it children who were shot dead at point blank?"
The death toll, including suspect 18-year-old Vladislav Roslyakov, rose to 21 on Thursday, Russian agencies cited the Russian Healthy Ministry as saying.
More than 40 others were injured in what local press dubbed "Russia's Columbine", a reference to a 1999 US high school massacre.
Russian authorities in Crimea were searching for a possible accomplice as well as looking to establish the motive for the attack.
The Investigative Committee said it was still working to establish the motive for the attack that recalled similar shooting sprees carried out by students in US schools.
Russia annexed Crimea from Ukraine in 2014, prompting international condemnation and Western sanctions, but since then there have been no major outbreaks of violence on the peninsula.
The Russia-backed government in Crimea published a list of the victims, most of whom were teenagers.
An ex-girlfriend told Russian state media Roslyakov had spoken to her about taking revenge for bullying at the school.
Globalisation to blame
Russian President Vladimir Putin said the mass school shooting in Crimea a day before was the result of "globalisation" and the continuation of an American trend.
"It's a result of globalisation. On social media, on the internet, we see that there is a whole community that has been created. Everything started with the tragic events in schools in the US," he said at a forum in Sochi.
He said unstable young people were creating "fake heroes for themselves" and "reaching out for a surrogate for heroism" in the absence of the real thing.
"We're not creating healthy (internet) content for young people... which leads to tragedies of this kind," he said.