Iran's Foreign Ministry said a U.S, citizen, Michael White, had been arrested in the city of Mashhad, according to the Islamic Republic News Agency.
Russia's FSB state security service said on Monday it had detained an American citizen suspected of spying in Moscow.
Boeing Co (BA.N), which is opening a 737 completion plant in China, will not display any of its planes but only models at its exhibition stand.
Two Iranian men were indicted on Monday for allegedly spying for Tehran in the United States.
U.S. President Donald Trump said that documents released by the FBI showed that his campaign for the 2016 presidential election had been illegally spied upon.
Yulia Skripal, who was poisoned in Britain last month along with her father, a former Russian spy.
Russia lost a bid Wednesday at the global chemical weapons watchdog to launch a joint probe with Britain into the spy poisoning scandal.
Russia's foreign intelligence agency chief Sergei Naryshkin said Washington's actions mean its possible to start speaking of a return to the Cold War.
Moscow has told Britain it must cut just over 50 more of its diplomatic and technical staff in Russia as a standoff deepened over the poisoning of a Russian spy.
Russia summoned a slew of senior Western diplomats on Friday to tell them how many of their embassy officials it was expelling in a worsening standoff.
Spy drama 'The Americans' takes final bow, timed to USSR's demise
European Union leaders backed Britain on Thursday in blaming Moscow over a nerve agent attack on a former Russian spy in England.
Ukraine's SBU security service said it has detained an aide to the country's Prime Minister Volodymyr Groysman on suspicion of being a Russian spy.
Iran's Revolutionary Guards have arrested at least 30 dual nationals during the past two years, mostly on spying charges.
Chinese authorities on Monday arrested a Japanese citizen suspected of spying, local state media said.
The famous spy duo of author John le Carre and his protagonist George Smiley are back for new adventures on Thursday .
Kuwaiti authorities have arrested 12 people convicted in absentia of spying for Iran and Lebanese Shi'ite Muslim group Hezbollah
The Chinese Foreign Ministry denied on Monday media reports that the American researcher sentenced to 10 years in prison for spying in Iran.
Arish Criminal court sentenced three Egyptians and six Israelis to life in prison Wednesday over charges of spying for the Israeli Military Intelligence in the case publicly known by the name Ovadia Cell