Kremlin admits Vadim Krasikov is a Russian state assassin

The Kremlin has admitted that Vadim Krasikov, the assassin freed by Germany in a historic prisoner swap on Thursday, is a serving officer of the Federal Security Service of the Russian Federation (FSB), essentially an acknowledgment that his 2019 murder of a Chechen exile in Berlin was a state-ordered hit.

It also hinted that he was linked to Vladimir Putin’s personal guard.

“Krasikov is an FSB employee,” Putin’s spokesperson, Dmitry Peskov, told reporters, adding that he had “served with some of the people working in the president’s security detail”.

Krasikov was one of eight Russians released from jails in the west and returned to Moscow on Thursday as part of a complex exchange deal in which 16 people were freed from Russian custody, including the US reporter Evan Gershkovich and several Russian opposition politicians.

Those involved in the negotiations have said that for Putin, Krasikov had always been the most important part of the puzzle, with the Kremlin insisting he would have to be part of any exchange.

Putin was described as “maniacal” about returning Krasikov from Germany by one source in Moscow with knowledge of the negotiations – and Friday’s admission goes some way to explaining why.

It is the first time the Kremlin has admitted one of its serving operatives is behind a murder on foreign soil. Previously, Moscow has always denied involvement in cases such as the 2006 poisoning of Alexander Litvinenko in London, the 2018 attempted murder of Sergei Skripal in Salisbury, or numerous hits on Chechen exiles in Istanbul , however implausible.

When Krasikov killed the Chechen exile Zelimkhan Khangoshvili in Berlin in 2019, the Kremlin denied all responsibility. “I categorically reject any link between this incident, this murder and official Russia,” Peskov said at the time . However, in an interview earlier this year, Putin referred to Krasikov as a “patriot” who had “liquidated a bandit”.

Krasikov and the other seven returnees to Russia – a mix of spies and those serving time on criminal charges – were given a hero’s welcome in Moscow after the exchange in Ankara, with a red carpet, a guard of honour and Putin arriving in person to offer embraces and bouquets of flowers as they stepped off the plane.

Peskov confirmed that Artem Dultsev and Anna Dultseva , who had been posing as an Argentine couple in Slovenia, were in fact Russian “illegals” – deep-cover spies who can spend decades abroad pretending to be foreigners. The couple’s two children, who had been taken into foster care when their parents were arrested in late 2022, travelled to Russia with them.

“The children of the illegals who arrived yesterday only found out they were Russian on the plane from Ankara. They do not speak Russian,” Peskov said. Putin greeted them in Spanish with the words “buenas noches” when they disembarked the plane.

The German chancellor, Olaf Scholz , who personally gave Joe Biden the green light for Berlin’s end of the deal, defended the prisoner swap as justified by a “duty to protect lives”, as Germany agonised over the high price of releasing Krasikov.

Related: Russia-US prisoner swap: Kremlin confirms hitman Vadim Krasikov worked for FSB security service – live

While during the cold war there were countless secret agent swaps across the Glienicke “Bridge of Spies” , the grand bargain pulled off on Thursday required Germany to open the prison gates for a man a Berlin court found had committed a “state-ordered killing” on German soil.

Vladimir Kara-Murza, a Russian-British citizen who was also freed by Moscow in the swap, acknowledged how difficult it had been for Germany to agree to release Krasikov but said the deal had saved “16 human lives”.

He also speculated that opposition leader Alexei Navalny might still be alive had the west agreed the swap with the Kremlin sooner.

“It’s hard for me not to think that, maybe if these processes had somehow moved quicker – if there had been less resistance – that the Scholz government had to overcome in terms of freeing Krasikov, then maybe Alexei would have been here and free,” he told reporters.

Another opposition activist, Ilya Yashin, described the deal as a “difficult dilemma for western governments”.

“It encourages Putin to take more hostages,” said Yashin, who was imprisoned for denouncing Moscow’s invasion of Ukraine.

Yashin had previously said he did not want to be exchanged, arguing that the voice of a Kremlin critic was more powerful in Russia than outside. But on Friday he vowed to continue his activism from abroad.

Related: Vadim Krasikov: who is Russian hitman linked to Navalny prisoner swap claim?

“I don’t know how to do Russian politics outside of Russia, but I will try to learn,” he said.

The prisoners’ liberation was greeted with joy and relief throughout Germany, but also hand-wringing by rights groups and outrage from the murder victim’s family.

Scholz, who broke off his holiday to greet 13 of the former detainees as they emerged from a private plane in Cologne, said he had no choice, given that the lives of at least some of the hostages had been at stake.

“No one took this decision lightly to expel a convicted murderer sentenced to life in prison after only a few years in custody,” he said.

After a “moving” meeting with those released, Scholz said speaking with them “now, in freedom, removed any doubt” over whether it had been the right thing to do.

Michael Roth, an MP in Scholz’s Social Democrats, said sometimes it was necessary “on humanitarian grounds to make a deal with the devil”.

The justice minister, Marco Buschmann, of the libertarian Free Democratic party, said the government had been required to make a “painful concession” in the form of Krasikov’s release order, a first, and one he personally had to sign.

Amnesty International , the human rights organisation, welcomed the exchange but warned of the precedent it could set.

“The Russian government could feel emboldened for further political arrests and human rights violations without having to fear consequences,” the deputy general secretary of the group’s German chapter, Christian Mihr, said.

Khangoshvili’s family reacted angrily to the swap, saying they had not been informed in advance. “It was devastating news for us relatives,” the family said in a statement through their lawyer, Inga Schulz.

Related: Russian prisoner swap deal was to have included Alexei Navalny

“On the one hand, we are happy that someone’s life has been saved. At the same time, we are very disappointed that there is apparently no law in the world, not even in the countries in which the law is meant to be the highest authority.”

Roderich Kiesewetter, an MP in the opposition Christian Democrats and a former Bundeswehr [German armed forces] officer, said the “danger of sabotage or terrorism by Russia could now rise” because Putin had shown that his henchmen had no consequences to fear.

The news magazine Der Spiegel said Putin had apparently calculated it would have been much harder to win Krasikov’s release if Donald Trump won the US election in November, given the former president’s frosty relationship with Berlin.

“Putin should have no problem finding helpers to hunt down undesirable people in the west,” it said. “They know: the boss will always get them home.”

Trump on Friday asserted that the swap was a “win for Putin” and that he as president would have been able to bring the Americans home without having to agree to an exchange.

“As usual, it was a win for Putin or any other country that deals with us, but we got somebody back, so I’m never going to be challenging that,” he told Fox . “We wouldn’t have had to pay anything. We wouldn’t have had to let some of the great killers of the world go, because that’s what’s happened, as you know.”

He hinted without evidence that the US had provided more than prisoners to Russia in the exchange.

“When you start paying money … when you start doing that, and all of a sudden you have a lot of hostages taken prisoner, so to speak, and you’ll have a lot of things happening,” Trump said. “It’s very bad. It’s a very bad precedent.”

Talks on a release of western inmates and Navalny in a swap for Krasikov had been held as early as 2022, soon after Moscow’s full-scale invasion of Ukraine began.

But, at the time Berlin resisted, with the hawkish foreign minister, Annalena Baerbock , leading opposition against a more amenable Scholz.

Baerbock, in particular, raised concerns that if Navalny were exchanged for Krasikov, Putin’s nemesis would probably soon return to Russia and be arrested again, leaving the west empty-handed, Die Zeit reported.

However, Scholz finally agreed to a major prisoner swap in February, telling Biden, “For you, I will do this.”

But by the end of that month Navalny was dead in a Russian penal colony. His fate was widely seen in the west as a warning for the other inmates in Russia, leading German diplomats and intelligence officials to redouble efforts to make a deal.