Hours before gunmen last week carried out the bloodiest attack in two decades in Russia, authorities made an addition to a government register of extremist and terrorist groups: They included the international LGBTQ+ “movement.”

That addition to the register followed a Russian Supreme Court court ruling last year that cracked down on gay and transgender people in the country.

While the register also lists al-Qaida and the Islamic State group, an affiliate of which claimed responsibility for the concert hall attack, the inclusion of LGBTQ+ activists raised questions about how Russia’s vast security services evaluate threats to the country.

The March 22 attack that killed over 140 people marked a major security failure under President Vladimir Putin, who came to power 24 years ago by taking a tough line against those he labeled terrorists from the Russian region of Chechnya waging a bloody insurgency.

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The lapse in security has led many to wonder how gunmen could easily kill so many people at a public event. One week after the massacre, here’s a look at what’s behind the failure to prevent the concert hall attack and the government’s chaotic response to it:

A FOCUS ON STIFLING DISSENT

Russia’s massive security apparatus has focused in recent years on stifling the political opposition, independent media and civil society groups in the harshest crackdown since Soviet times. The repressions have only intensified after the invasion of Ukraine.

Individual protesters are swiftly quashed by riot police. After the Feb. 16 death of opposition leader Alexei Navalny in prison, mourners bringing flowers and candles to makeshift memorials were quickly detained. Surveillance cameras with facial recognition software are widely used.

Many opposition groups have been branded as “extremists” -– a designation that carries long prison terms for anyone associated with them.

Navalny was serving a 19-year sentence on charges of extremism, and his political network is on the register of extremist and terrorist organizations, just like the LGBTQ+ “movement” that on March 22 was added to the register of Russia’s state watchdog for financial crimes.

Top Navalny associate Leonid Volkov, who lives abroad, said the security agencies are too busy with the political crackdown to pay attention to terrorism threats.

“They like inventing fictitious terrorists -- those who think or love differently -- so they don’t have time for real ones,” he said on his messaging app channel.

Many security officers are focused on suspected Ukrainian agents and fending off sabotage and other attacks by Ukraine in the 2-year-old war. They also are scouring social media for signs of anti-war sentiment.

After the attack, law enforcement agencies followed a familiar pattern of repression, detaining people over social media posts about it that authorities deemed offensive.

Andrei Kolesnikov, senior fellow at Carnegie Russia Eurasia Center, said security forces focused on Kremlin critics but have proven inadequate in tackling real threats to the country.

“This machine can’t be effective when it has to perform its direct function to ensure citizens’ security,” he wrote in a commentary, noting Putin has had nearly a quarter- century to ensure “stability and security, but instead he ruined both.”

A U.S. WARNING DISMISSED AS ‘BLACKMAIL’

The U.S. government said it told Russia in early March about an imminent attack under the “duty to warn” rule that obliges U.S. intelligence officials to share such information, even with adversaries. It was unclear how specific it was.

The U.S. Embassy in Moscow also issued a public notice March 7 advising Americans to avoid crowds in the capital over the next 48 hours due to “imminent” plans by extremists to target large gatherings, including concerts.

With Russia-U.S. relations at their lowest point since the Cold War, Moscow was likely to treat any such tip with suspicion. Three days before the attack, Putin dismissed the U.S. Embassy notice as an attempt to scare or intimidate Russians and blackmail the Kremlin.

Alexander Bortnikov, head of the Federal Security Service, or FSB, said the U.S. warning was general and didn’t help track down the attackers. He said the FSB, acting on the tip, targeted some suspects but it proved wrong.

Putin and other officials tried to divert attention from the security failure by seeking to link the attack to Ukraine despite Kyiv’s emphatic denials and the Islamic State affiliate’s claim of responsibility.

In a persistent attempt to blame Kyiv, investigators alleged the attackers had received cash and cryptocurrency from Ukraine and arrested a man accused of involvement in the transfers. They didn’t provide any evidence.

A BUNGLED INITIAL RESPONSE

It took anti-terrorism units at least a half-hour to reach the concert hall after hearing of the attack. By that time, the gunmen had fled after setting fire to the venue.

The security forces’ arrival at the concert hall on Moscow’s outer ring road was delayed by rush hour traffic, and it took them time to assess the situation as concertgoers fled.

Police said they were able to check security video before the building was destroyed and quickly saw the gunmen. Cameras caught them arriving at the hall and then departing in a white Renault. Russian media said the car was continuously caught by traffic cameras as it sped from Moscow.

It wasn’t immediately clear why authorities allowed them to drive more than 370 kilometers (over 230 miles) southwest before finally arresting them about 140 kilometers (86 miles) from the Ukrainian border.

A CONFUSING AND MIXED KREMLIN MESSAGE

After the Islamic State’s branch in Afghanistan claimed responsibility, Putin at first did not mention the group on the day after the attack. On Monday, he acknowledged “radical Islamists” were behind the attack but also repeated — without evidence — that Ukraine and the West were likely involved. Those allegations were echoed by his security chiefs.

He and his lieutenants said the arrest of the four gunmen near Ukraine indicated Kyiv’s likely involvement, ignoring Ukrainian denials and the IS statement.

Belarus’ authoritarian President Alexander Lukashenko, a close Moscow ally, declared that he and Putin had discussed bolstering the Russia-Belarus border to prevent the attackers from crossing — muddling the Kremlin claims of a Ukrainian escape route.

A TROUBLED MANHUNT

The four suspects were detained, along with seven others, with a search for more accomplices underway. Putin also ordered investigators to find the masterminds, a task that appears challenging.

A senior Turkish security official said Tuesday that two of the four suspects spent a “short amount of time” in Turkey before traveling together to Russia on March 2.

In video released by Russian news outlets, one of the suspects told interrogators he had been contracted for the attack by an associate of an Islamic preacher who offered him 1 million rubles (about $10,800).

The veracity of the suspects’ statements has come into question after they showed signs of severe beatings. At a court hearing Sunday night, their faces appeared swollen and bruised. One had a heavily bandaged ear -– reportedly cut off during an interrogation — another had a plastic bag hanging over his neck and a third was in a wheelchair with his eyes closed, accompanied by medical personnel.

A POSSIBLE AFTERMATH

Putin’s allegations of Ukrainian involvement in the attack could set the stage for him to both raise the stakes in the war and to further tighten the crackdown on critics at home.

But he is unlikely to reshuffle the leadership of security agencies, despite the embarrassing blunders that led to the security lapses.

Putin is known to resent making personnel changes under pressure, which could make him look weak. During stage-managed televised meetings with top officials to discuss the attack, he avoided any criticism of their performance, indicating their jobs are safe at least for now.

With leading opposition activists in prison or abroad and independent media muzzled, Putin this month rode a stage-managed election landslide to another six years in power. That will keep him well-insulated from any public criticism.

Compliant lawmakers and state-controlled broadcasters and other media will continue to hammer home his message of Ukraine’s alleged role in the attack, distracting attention from the poor performance of law enforcement agencies.