In a remarkable one-two punch aimed at Russian hackers, bots and trolls, the prime ministers of Britain and Spain have separately accused Russian entities — including some allegedly supported by the state — of meddling in European elections and have vowed to foil them.

Spanish Prime Minister Mariano Rajoy said Tuesday that an “avalanche” of bots spread “fake news” about Spain during Catalonia’s independence referendum last month and that Spanish authorities think that more than half of the originating accounts are in Russian territory.

British Prime Minister Theresa May on Monday night charged that President Vladimir Putin's Russia was attempting to "undermine free societies" and "sow discord" in Britain and among its Western allies by "deploying its state-run media organizations to plant fake stories."

“So I have a very simple message for Russia,” May said. “We know what you are doing. And you will not succeed.”

The allegations leveled by May and Rajoy stand in stark contrast to remarks made over the weekend by President Trump, who appeared to defend the Russian president.

“He said he didn’t meddle,” Trump said Saturday, answering reporters’ questions on Air Force One about growing evidence of Russia’s involvement in the 2016 U.S. presidential campaign. “I asked him again. You can only ask so many times. . . . He said he absolutely did not meddle in our election. He did not do what they are saying he did.”

Trump said he believed Putin was “sincere” in his denials and that the Russian president even felt insulted by the accusation.

Russian officials responded to the statements from London and Madrid by calling them unsubstantiated, hypocritical and in keeping with a “blame Russia first” ethos in the West.

In their remarks, neither Rajoy nor May provided much evidence to support their accusations, although both countries have deployed their security services to investigate the alleged peddling of fake news.

“We learned that 55 percent of those fake profiles were in Russia,” Rajoy told the Cope radio network on Tuesday, discussing social avatars and accounts. “And an additional 30 percent in Venezuela. This has happened with Brexit [and] in the French elections with Le Pen” — a reference to the nationalist party leader who lost a presidential runoff vote to Emmanuel Macron in May.

Rajoy said he had no information that the Russian government was behind the false accounts.

Spanish authorities have said that Russian users falsely linked images of violence to the controversial referendum and amplified news accounts from state-backed Russian media outlets that stoked separatism.

“What is clear is that there are people who may be interested in things not going well in Europe,” Rajoy said.

Catalan pro-independence advocates deny that Russian bots played a significant role in bolstering their cause.

Preliminary investigations by a Spanish media outlet found that social media at the time of the unconstitutional referendum were awash in fake news and unrelated images circulated by both sides — pro-independence activists and those opposed to secession from Spain.

May’s condemnation of Russia, in a speech to business leaders at an annual London banquet, reflected her government’s concern that Russia continues to manipulate social media, efforts that “included meddling in elections and hacking the Danish Ministry of Defense and the Bundestag, among many others,” the prime minister said.

“The U.K. will do what is necessary to protect ourselves, and work with our allies to do likewise,” May said.

Yin Yin Lu of the Oxford Internet Institute told the Times of London that 54 accounts on a list of 2,752 linked by Twitter to the Internet Research Agency had tweeted about “Brexit,” Britain’s planned exit from the European Union. The Internet Research Agency is a shadowy cyberspace operation, based in St. Petersburg, that U.S. and some Russian investigators say has ties to the Kremlin.

May's remarks appeared to contradict her foreign secretary, Boris Johnson. Asked earlier this month whether he suspected that Russia played a role in recent British elections, Johnson answered: "No, I haven't seen any [evidence], not a sausage. . . . As far as I know they have played no role," according to the Reuters news agency.

In Spain, some seemingly automated Twitter accounts do appear to have tweeted news stories about the referendum from Sputnik and RT (formerly Russia Today), two Kremlin-backed news organizations that often promote narratives about the supposed weakness of Western institutions.

Javier Lesaca, a visiting scholar at George Washington University’s School of Media and Public Affairs, wrote Sunday in Spain’s El País newspaper that many of the 65 Twitter accounts he studied that were sharing RT and Sputnik stories on Twitter appeared to be automated bots.

He cited three specific Twitter accounts, each of which had fewer than 2,000 followers and appeared to share the same RT and Sputnik stories simultaneously, mostly in English rather than Spanish or Catalan.

Spanish Foreign Minister Alfonso Dastis, asked Monday in Brussels whether his government had evidence to back up its accusations, said, “Yes, we have proof,” Reuters reported. Dastis did not offer specifics beyond the figures Rajoy cited.

Leaders outside Spain have been cautious in their assessments of the situation.

The European Union’s top diplomat, Federica Mogherini, and NATO Secretary General Jens Stoltenberg declined to comment Monday when asked about possible Russian meddling in the Catalan independence effort.

Last week, the top military official in the NATO defense alliance, Supreme Allied Commander Curtis Scaparrotti, said that Russia had been trying to influence Western political systems, but he did not directly address the situation in Catalonia when asked about it.

A senior Russian lawmaker on Tuesday called May’s comments “baseless accusations” against Russia. “In normal life, people are held responsible for slander and mudslinging, but there is the ‘Russians-did-it’ presumption of modern diplomacy,” the chairman of the foreign affairs committee of the upper house of Russia’s parliament, Konstantin Kosachev, wrote on Facebook. “Why bother giving any facts or proof?”

Another Russian senator also dismissed May’s charges.

“The world order that pleases May, with the seizure of Iraq, war in Libya, the rise of IS and terrorism in Europe, has outlived itself,” Alexei Pushkov tweeted, using a reference to the Islamic State. “You cannot save it by attacking Russia.”

Birnbaum reported from Brussels. Pamela Rolfe in Madrid contributed to this report.

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