During the Soviet era, the country’s top computer scientists and programmers largely worked for the secret services.

That practice appears to have resumed under President Vladimir Putin, as Russia faces accusations of waging a global campaign of cyber attacks. Dutch officials on Thursday accused four Russians from the GRU military intelligence agency of attempting to hack into the global chemical weapons watchdog in The Hague.

The agency has investigated both the fatal poisoning of Russian former double-agent Sergei Skripal; and an alleged chemical attack by Moscow-allied Syrian President Bashar al-Assad. The Baltic states were the first to accuse Moscow of mounting attacks to knock out their sites back in 2007.

Estonia said one such attack had put the country’s main emergency service phone number out of action for over an hour. Since then, accusations of cyber attacks have continued against Moscow.

The Russian hacker group variously known as Fancy Bear, APT 28 and Sofacy has been linked to GRU and accused of attacks on the US Democrats’ 2016 presidential campaign, together with Russia’s FSB security service, the successor to the KGB. The skills of Russian hackers today developed from a tradition of excellent computing and programming skills dating back to the Soviet era.

“The whole structure of the economy was skewed towards the military sector,” said Oleg Demidov, a consultant at the Moscow-based independent think-tank PIR Center.

“All the achievements of Soviet science including the first computers went to serve the military sector.” The most brilliant students were pushed to work in the military and space sector, he added.

After the Soviet Union fell apart in 1991, its armed forces were broken up and most of the top specialists turned to the nascent banking sector in Russia, either to work there or to attack it. In this era saw the first cyber attacks on banking operations and the first mentions of Russian hackers.

“Now Russian hackers are excellently trained and equipped and they still occupy one of the top positions in banking crime,” said Demidov — even if the Russian justice system has begun to crack down on them.

In 2016, Russian cybersecurity giant Kaspersky estimated that between 2012 and 2015, Russian hackers had stolen at least $790 million worldwide.