Kevin Hagen/Getty Images(WASHINGTON) — Secretary of State Mike Pompeo on Wednesday addressed concerns from family members of an American man arrested in Russia on spying charges, saying the U.S. aims to get him consular access and has requested more information from Russia on “what it is he is accused of.”

“We’ve made clear to the Russians our expectation, that we will learn more about charges and come to understand what it is he is accused of, and if the detention is not appropriate we will demand his immediate return,” Pompeo said after a meeting with incoming Brazilian Foreign Minister Ernesto Araujo.

Russian authorities detained American citizen Paul Whelan on Friday over accusations of spying, according to Russia’s Federal Security Service (FSB).

International treaties mandate that detained Americans be given access to U.S. consular officers for legal guidance.

Whelan, a former staff sergeant in the U.S. Marines, was in Russia to attend a wedding, his family said. His friends later became concerned after he failed to show up at the wedding.

Whelan’s family has denied he is a spy and said they’re concerned for his safety.

“He’s got a military background, he’s been in corporate security for years. He was former law enforcement. He was going to be very well aware of the risks of traveling in Russia,” Paul Whelan’s brother, David Whelan, told ABC News on Tuesday. “I just don’t see him putting himself in a position where he would be considered to break the law by a government like Russia’s.”

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