Thousands of residents were expected to attend the funerals of most of the victims Friday. The burials are taking place in mainland Russia, which annexed Crimea from Ukraine in 2014.
Little information has emerged about the 18-year-old gunman, Vladislav Roslyakov. Authorities said they were investigating if he had an accomplice in Wednesday's shotgun massacre at Kerch Polytechnic College.
Teachers and classmates have described him as a shy person with few friends. A computer taken from the home where Roslyakov lived with his parents revealed little, a Crimean official said Thursday.
"When they did a search and saw the computer, all information, messages and such had been deleted," Crimean human rights ombudswoman Lyudmila Lubina was quoted as saying by Russian news agency Tass.
Roslyakov was initially described as the only person involved in the carnage at the school. But Sergei Aksyonov, the Kremlin-appointed head of Crimea, told Russian news agencies Thursday it's still possible the student had help.
"The point is to find out who was coaching him for this crime," Aksyonov said. "He was acting on his own here, we know that. But this scoundrel could not have prepared this attack on his own, in my opinion, and according to my colleagues."
Residents brought flowers and toys to a makeshift memorial outside the school on Thursday morning. Many were in tears, struggling to speak.
The Kerch attack was by far the deadliest carried out by a student in Russia, raising questions about school security. The vocational school had a front desk, but no security guards. Russia's National Guard said Thursday it has now deployed officers and riot police to all schools and colleges in Kerch.
Wednesday's violence also was the deadliest school attack in Russia since the 2004 Beslan attack by Chechen separatists, which left 333 people dead, many of them children, during a three-day siege. Hundreds of others were wounded.
As the day wore on Thursday, neither Russian investigators nor other authorities followed up on Aksyonov's comments hinting at a wider attack plot. President Vladimir Putin, meanwhile, portrayed the mass shooting in Kerch as a "result of globalization" - forces that were exporting bad practices into Russia.
Speaking at an international policy conference, Putin compared Roslyakov's assault to the numerous school shootings in the United States. In the past few years, authorities have said several school attacks in Russia allegedly were inspired by gun violence in the U.S.
Putin said that in his view, teenagers getting guns and going on shooting rampages meant adults had failed to offer them alternatives to violence.
"Young people with a fragile mental state are creating false heroes for themselves," he said. "That means that all of us, not only in Russia, but in the world on the whole, are reacting poorly to the fast-changing realities."
Russia has fairly strict gun legislation. Civilians can own only hunting rifles and smoothbore shotguns and must undergo significant background checks. Roslyakov had only recently received a permit to own a shotgun and had bought 150 cartridges just a few days ago, according to local officials.
Asked about possible plans to further restrict gun ownership in Russia, Kremlin spokesman Dmitry Peskov said the government would wait for the results of the Kerch investigation.
Since Russia annexed the Crimean Peninsula from Ukraine, Russian authorities repeatedly warned of a terrorism threat from unnamed Ukrainian nationalists and ethnic Tatars, an indigenous Crimean people. But despite acts of public defiance and rallies, both groups haven't engaged in any violent activities in Crimea.
The death toll in Kerch, excluding Roslyakov, climbed Thursday to 20 after one of the wounded died in a hospital, according to Russian news agency Tass.
Dozens of people remained hospitalized in Kerch, and at least 10 with severe injuries were being airlifted to top Russian hospitals for surgery, Health Minister Veronika Skvortsova said.
Most victims died from gunshot wounds, authorities said. Many others had wounds from an improvised explosive device that went off packed with shrapnel. Skvortsova said some victims had their legs or feet blown off.
"The kids' muscles have been 'minced' with small metal objects," Skvortsova said. "In those who have their organs ripped apart, we are finding metal balls in kidneys, intestines, in blood vessels. That is how powerful the blast was."
Taisiya Roslyakova, the grandmother of the young man said to have carried out the attack, told the Komsomolskaya Pravda daily Thursday that her grandson was a kind boy who always helped her with chores, unlike his father.
She said Roslyakov did not have many friends and spent all his time indoors playing computer games. She said she last saw him a week ago when he stopped by and asked if he could take all the family photo albums.
Vladimir Isachenkov and Jim Heintz in Moscow contributed.
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