[32] Colin Clarke from the independent Soufan Center think tank said that IS–KP "has been fixated on Russia for the past two years, frequently criticizing Putin in its propaganda.

[33] On 7 March, the Russian Federal Security Service (FSB) announced that it had neutralized an Islamic State terrorist cell in Moscow, which had intended to attack a synagogue in the city.

[27] In contrast, the Russian ambassador to the United States, Anatoly Antonov, said that in regards to the attacks "no concrete information, nothing was passed to us",[40] while the head of the FSB, Alexander Bortnikov, said that the US warning was "of a general nature".

[43] Ten days after the attack, it was reported that Iran had also warned Russia that a major "terrorist operation" was being planned, based on information gathered from IS militants arrested after the Kerman bombings.

[45] It is part of a larger block of shopping centers, restaurants, and other attractions called Crocus City,[46] which was built by Azerbaijani billionaire and property developer Aras Agalarov[47] and was also the venue of the Miss Universe 2013 pageant and the Top Hit Music Awards in 2013 and 2019.

[56] A part-time cloakroom assistant, 15-year-old Islam Khalilov, reportedly helped save more than a hundred concert-goers by showing them an exit through the venue's office space.

[104] State Duma deputy Alexander Khinshtein said that Tajik passports were discovered in the vehicle of the individuals in custody,[31] and the Russian Telegram channel Baza identified the four attackers as citizens of Tajikistan.

[109] On 12 April however, Tajikistani foreign minister Sirojiddin Muhriddin issued a statement condemning the alleged torture of the suspected attackers in Russian custody, calling it "unacceptable".

[111] On 24 March, four suspects, Dalerjon Mirzoyev, 32; Saidakrami Rachabalizoda, 30; Shamsidin Fariduni, 25; and Muhammadsobir Faizov, 19, appeared at Basmanny District Court in Moscow and were charged with terrorism.

[121][62] In another interrogation video released by Russian state media, Fariduni said that he participated in the attack in exchange for 1 million rubles ($11,005), half of which he claimed to have already received by card transfer from individuals who contacted him on Telegram and whose identities he did not know.

[131] According to Turkish media, the mentioned terrorist organization was based in an illegal mosque or madrasa called Darul Vefa İlim ve Amel Merkezi (Muvahhid Derneği) in Başakşehir, Istanbul.

[139][140][141] On 31 March, the FSB announced the arrest of four people in Makhachkala and Kaspiysk in Dagestan on suspicion of providing funds and weapons to the attackers at Crocus City Hall.

[147] On 27 April, Russian authorities announced that charges were filed against a twelfth suspect for allegedly providing communications logistics and financing to the attackers.

[180] Despite a police cordon, passers-by laid tributes outside Crocus City Hall following the attack,[181] while advertising billboards in Moscow displayed memorial posters showing a candle and the message Skorbim ("We mourn").

[63][99][187] Sberbank, Sovcombank, and Home Bank pledged to settle loans and relieve the debts of the families of clients who were killed or injured in the attack.

[58][57] A friendly football match between Russia and Paraguay scheduled on 25 March at the VTB Arena in Moscow was postponed indefinitely due to the attack.

In Moscow, local government employees advised immigrant street cleaners against going outside on 24 March because of "mass police raids against Tajiks and Uzbeks on the day of mourning".

[209] Several pro-government news outlets such as Readovka began sending the message that "not all Tajiks are terrorists" and "disturbing the interethnic harmony in Russia and making us hate each other is the goal of our real enemies, Ukraine and the West".

[210] Sergei Mironov, the leader of A Just Russia – For Truth, called for the establishment of a visa regime, saying "It is necessary to regulate migration and counter terrorist attacks.

[219] On 26 March, Putin's claims were seemingly contradicted by his close ally, Belarusian president Alexander Lukashenko, who said the attackers had first tried to cross into Belarus.

[226][228] On 23 March, Ukrainian President Volodymyr Zelenskyy said that Putin, "instead of dealing with his citizens of Russia, addressing them...remained silent for a day – thinking how to bring this to Ukraine.

[214] The US said there was no indication of Ukrainian involvement,[37][230] while UK Chancellor of the Exchequer Jeremy Hunt called the Russian allegations "a smokescreen of propaganda to defend an utterly evil invasion of Ukraine.

[232] Putin, who previously said the attack was caused by "radical Islamists" aided by the U.S. and Ukraine, later said that the act was not one of Islamic terrorism, as it demonstrated "a unique example of interfaith and interethnic unity".

[233] On 6 April, the Tajikistani foreign ministry denied claims by Russian officials that Ukraine was recruiting mercenaries in the country through its embassy in Dushanbe.

[241] Navalny associate Ivan Zhdanov criticised Russian security services for their "catastrophic incompetence" and the FSB for being "busy with everything except its direct responsibilities – killing their political opponents, spying on citizens and prosecuting people who are against the war."

[242] Novaya Gazeta Europe's chief editor, Kirill Martynov, criticized Putin for dismissing Western intelligence warnings and focusing resources on "LGBT extremists" and the war with Ukraine instead of guarding against "real threats".

[205] Opposition activists and human rights groups also criticized the torture inflicted on the suspects in the attack, with Sergei Davidis of Memorial saying that Russian security services had "decided that this time there are no reasons to conceal their methods", adding that it was a "bad sign".

[243] Tatyana Moskalkova, Russia's Commissioner for Human Rights, also said that it was "absolutely inadmissible to use torture against detainees and accused persons", and reiterated that "any procedural operational actions must be carried out in accordance with the law".

[249][9][250] The British embassy in Moscow condemned the attack and expressed its "sincere condolences to the relatives and loved ones of those hurt and killed in today's events.

[265][266] On 24 March, the French government raised its security alert to its highest level, with Prime Minister Gabriel Attal citing the Crocus City Hall attack as one of the reasons.