Following China's 'reactions' to the detention of Huawei CFO Meng Wanzhou, and the ongoing (and escalating) tensions between Washington and Moscow over Crimea among other things, The Guardian reports that Russia has detained a US citizen in Moscow accused of spying.

FSB HQ in Moscow

According to a statement from the FSB security service (Russia's domestic agency), the American was detained on Friday “while carrying out an act of espionage” and a criminal case has been opened.

"The investigation department of the Federal Security Service of Russia initiated a criminal case against a US citizen under article 276 of the Criminal Code of the Russian Federation. The investigation is underway," the statement continued.

Article 276 is espionage.

The statement identified the American in Russian, using a name that appeared to translate as Paul Whelan. No other details were immediately available.

The U.S. Embassy in Moscow could not immediately be reached for comment.

If found guilty, Whelan faces 10 to 20 years imprisonment, Russia's state-run news agency TASS reported.