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The logo for LinkedIn Corporation is shown in Mountain View, California Reuters/Robert Galbraith

Czech police have arrested a Russian hacker suspected of hacking targets in the United States, officials said on Tuesday (18 October). LinkedIn said on Wednesday that the arrest, carried out in cooperation with the FBI, was related to the massive 2012 hack on LinkedIn that compromised over 100 million users' information, including emails and passwords.

''Following the 2012 breach of LinkedIn member information, we have remained actively involved with the FBI's case to pursue those responsible," LinkedIn said in a statement. "We are thankful for the hard work and dedication of the FBI in its efforts to locate and capture the parties believed to be responsible for this criminal activity."

Yevgeniy N, born in 1987, was arrested at a central Prague hotel on 5 October in response to a "red notice" issued by Interpol and could face extradition to the US. Wearing a hooded sweatshirt with camouflage pattern, blue jeans and sneakers, the man was arrested without resistance, police said. He was briefly in hospital after collapsing and then taken into custody.

Police spokesman David Schoen told the Associated Press that the announcement of the arrest was delayed for "tactical" reasons.

The suspect's possible extradition to the US will be decided by Prague's Municipal Court where Justice Minister Robert Pelikan will have the final say. However, Russian officials have demanded that the suspected hacker be handed over to them.

Russian state news agency Tass quoted Andrei Kolmakov, a spokesman for the Russian embassy in Prague, as saying it insists that the suspect be handed over to them.

"The embassy has been taking all necessary efforts to protect the interests of this Russian citizen. We are in contact with his attorney," the embassy statement said. "Russia repudiates Washington's policy of imposing its extraterritorial jurisdiction on all countries. We insist that the detainee is handed over to Russia."

US and Czech authorities have not specified the charges being filed against the man and have reportedly declined to confirm if he is a suspect in the LinkedIn data breach.

The FBI said in a statement on Wednesday that the man was "suspected of conducting criminal activities targeting US interests," but did not provide any further details. "As cybercrime can originate anywhere in the world, international cooperation is crucial to successfully defeat cyber adversaries," it added.

In May, LinkedIn confirmed that the much-publicised mega data breach in 2012 compromised more user accounts than previously thought, urging millions of users to reset their passwords and enable two-step verification. At the time of the hack, it reported that 6.5 million email and password combinations were compromised.

The stolen user credentials were put up for sale on the Dark Web earlier this year by a hacker going by the name "Peace."

Two US law enforcement officials told Reuters that the new arrest is not related to the recent hacks of the Democratic National Committee or other political organisations that Washington recently accused Russia of orchestrating in an attempt to interfere in the upcoming 8 November presidential election. Russian President Vladimir Putin has denied any involvement by the Russian government in the cyberattacks.