KYIV, March 30 - Russia’s security service arrested an American reporter for The Wall Street Journal on espionage charges, the first time a U.S. correspondent has been detained on spying accusations since the Cold War. The newspaper denied the allegations and demanded his release.

Evan Gershkovich, 31, was detained in Yekaterinburg, Russia’s fourth-largest city, about 1,670 kilometers (1,035 miles) east of Moscow, The Associated Press reported. Russia’s Federal Security Service accused him of trying to obtain classified information.

Known by the acronym FSB, the service is the top domestic security agency and main successor to the Soviet-era KGB. It alleged that Gershkovich “was acting on instructions from the American side to collect information about the activities of one of the enterprises of the Russian military-industrial complex that constitutes a state secret.”

The Journal “vehemently denies the allegations from the FSB and seeks the immediate release of our trusted and dedicated reporter, Evan Gershkovich,” the newspaper said. “We stand in solidarity with Evan and his family.”

The arrest comes at a moment of bitter tensions between the West and Moscow over its war in Ukraine and as the Kremlin intensifies a crackdown on opposition activists, independent journalists and civil society groups.

The sweeping campaign of repression is unprecedented since the Soviet era. Activists say it often means the very profession of journalism is criminalized, along with the activities of ordinary Russians who oppose the war.

Earlier this week, a Russian court convicted a father over social media posts critical of the war and sentenced him to two years in prison. His 13-year-old daughter was sent to an orphanage.

Gershkovich is the first American reporter to be arrested on espionage charges in Russia since September 1986, when Nicholas Daniloff, a Moscow correspondent for U.S. News and World Report, was arrested by the KGB. Daniloff was released without charge 20 days later in a swap for an employee of the Soviet Union’s United Nations mission who was arrested by the FBI, also on spying charges.

Gershkovich, who covers Russia, Ukraine and other ex-Soviet nations as a correspondent in the Journal’s Moscow bureau, could face up to 20 years in prison if convicted of espionage. Prominent lawyers noted that past investigations into espionage cases took a year to 18 months, during which time he may have little contact with the outside world. (ap/ez)