A flag flies behind an enclosure on the territory of the U.S. embassy in Moscow, Russia March 28, 2018. REUTERS/Tatyana Makeyeva - UP1EE3S16VMMC
A flag flies behind an enclosure on the territory of the U.S. embassy in Moscow, Russia March 28, 2018. REUTERS/Tatyana Makeyeva - UP1EE3S16VMMC

MOSCOW - Paul Whelan, the American citizen detained in Moscow on Friday on espionage charges, has been identified as a retired U.S. Marine.

Whelan's family posted messages on social media Tuesday, saying they first grew concerned when he did not contact them on Friday.

"'We have read reports of the arrest in Moscow of Paul Whelan, our son & brother," the statement reads. "Paul is a retired Marine and was visiting Moscow to attend a wedding."

The family learned of his arrest only after it was reported by Russian state news outlets, prompting the family to contact congressional representatives and U.S. diplomats.

"We are deeply concerned for his safety and well-being," the family said. "His innocence is undoubted and we trust that his rights will be respected."

On Monday, Russian Federal Security Service (FSB) officials said Whelan had been detained on December 28 "while carrying out an act of espionage," and that they have opened a criminal probe.

They provided no further details, but Russia's state-run TASS news agency said that Whelan faces up to 20 years in prison if convicted.

A State Department spokesperson said Monday the United States is aware of Russian authorities' detention of a U.S. citizen.

"We have been formally notified of the detention by the Ministry of Foreign Affairs," the official said in an emailed statement to VOA. "Russia's obligations under the Vienna Convention require them to provide consular access. We have requested this access and expect Russian authorities to provide it." The State Department did not provide further details, citing privacy concerns.

Tensions between Moscow and the West

The arrest coincides with several spy scandals that have exacerbated tensions between Russia and the West, including the poisoning of former double agent Sergei Skripal and his daughter in Britain, along with the recent U.S. conviction of Russian citizen Maria Butina for acting as an illegal foreign agent.

Public figure Maria Butina (R) attends a meeting o
Public figure Maria Butina (R) attends a meeting of a group of experts, affiliated to the government of Russia, in this undated handout photo obtained by Reuters on July 17, 2018.

Butina pleaded guilty to acting under the direction of a Russian official to establish relationships with influential Americans.

News of Whelan's detention came less than 24 hours after Russian President Vladimir Putin issued a New Year's greeting to U.S. President Donald Trump in which he said Moscow is amenable to a continuing dialogue with Washington on a range of topics.

In 2016, Izvestia, a Kremlin-aligned news outlet, reported that there were 13 U.S. citizens in Russian jails at the time. The Kremlin has not since published any details on other Americans currently in Russian detention.