In July, on Mr Putin's orders, Russian security services also won official permission to hunt terrorists abroad.
State-run media also posted a series of photos released by Russian security services that purportedly showed Mr. Fogle's detention.
An unnamed official told the AP news agency that US investigators were working with the Russian security services, the FSB.
Russian security services killed Abu Dujana in December during an assault on an apartment in Makhachkala, the capital of Dagestan.
Russian security services have declined to confirm that they warned the U.S. or ever had the alleged bomber on their radar.
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In May 2012, Russian security services caught up with Mr. Nidal, killing him in a shootout at an apartment on the outskirts of Makhachkala.
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Russian security services killed Dolgatov in December during an assault on an apartment in Makhachkala, the capital of the Russian Caucasus republic of Dagestan.
The newspaper said the men had social networking ties that brought Tsarnaev to the attention of Russian security services for the first time in late 2010.
The official would give no further details about what the Russian security services knew about Tsarnaev's activities in Dagestan or about any possible connection to Plotnikov.
Russian security services, however, had Mr. Tsarnaev in their sights.
The Kremlin said Russian security services gathered little information on Mr. Tsarnaev, but officials in the province of Dagestan said they tracked him during a six-month trip there in 2012.
Levy wrote a lengthy article in the New York Times about how Russian security services arrested members of an environmental group under the pretense that they were using pirated Microsoft software.
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"Seeing as the Tsarnaev brothers didn't reside in Russia, our security services couldn't have provided meaningful operational information to our foreign partners, " Interfax quoted a "source in the Russian security services" as saying Saturday.
Still, Russian security services are questioning him about his relationship with Mr. Tsarnaev, said a person close to Mr. Kartashov, who was arrested last week by police in Kizlyar for leading what they said was an illegal rally at a wedding.
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Authorities arrested three men this week in Georgia's breakaway republic of Abkhazia on charges of plotting the attack in a joint operation with Abkhazian security services, the Russian National Anti-Terrorism Committee said, according to the state-run RIA Novosti news agency.
With the two governments deadlocked over the Litvinenko case, British officials say there is no prospect of reversing a ban on co-operation between their security services, or of easing visa restrictions for Russian officials (a big source of annoyance in Moscow).
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Gertz quotes John Shaw, the Deputy Under Secretary of Defense for International Technology Security, who contends - based on information from two reliable European intelligence services - that Russian troops and Iraqi intelligence "almost certainly" removed the missing material from the facility.
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