FBI agents pore over bombing suspect’s trip to Russia in 2012

Officials investigate Tamerlan Tsarnaev’s visit to Dagestan

FBI agents are working closely with Russian security officials to reconstruct Tamerlan Tsarnaev’s activities and connections in Dagestan during his six-month visit last year, tracking meetings he may have had with specific militants, his visits to a radical mosque and any indoctrination or training he may have received, law enforcement officials said on Sunday.

At the same time, the bureau is also still looking for “persons of interest” in the United States who may have played a role in the radicalization of Tsarnaev, 26, and his younger brother Dzhokhar, 19, before the Boston Marathon bombing on April 15, Rep. Mike Rogers, R-Mich. and chairman of the House Intelligence Committee, said on ABC News’ “This Week” on Sunday. But Rogers said “the big unknown” remains what happened in Russia.

Investigators believe it is likely that the Tsarnaev brothers were self-radicalized and got their bomb-making instructions strictly from the Internet. But they are still exploring the possibility that other people in Russia or the U.S. were critical influences, if not accomplices, and officials say it may be weeks before the full picture of their plot is clear.

Officials said they were still examining the conduct of the Tsarnaev brothers’ mother, Zubeidat Tsarnaeva, and Tamerlan’s wife, Katherine Russell, 24, who converted to Islam when she married him in 2010.

On Saturday, the Russian investigative newspaper Novaya Gazeta reported that Tamerlan Tsarnaev had sought to join the Muslim insurgency in Dagestan and had been in contact with several rebels who were killed by Russian authorities in late spring of 2012 while he was staying in Makhachkala, the regional capital.

Tamerlan Tsarnaev left Dagestan in July 2012, just two days after a shootout between militants and the police in which several militants were killed, including William Plotnikov, 23, a Russian-born Canadian, and like Tsarnaev, an amateur boxer. Investigators are trying to determine whether Tsarnaev and Plotnikov met, one official said Sunday.

In 2011, Russian officials sent a warning about Tamerlan Tsarnaev’s extremist views to both the FBI and the CIA, saying they believed he was coming to Dagestan, a republic in southern Russia, to connect with underground groups. That warning was based on telephone conversations intercepted by Russian intelligence, including one between Tamerlan Tsarnaev and his mother, in which they discussed jihad, Russian authorities have told the FBI.

Experts on the effort by Russian authorities to contain the Muslim insurgency in Dagestan and elsewhere in the North Caucasus region said that if officials were aware of Tsarnaev’s arrival in Dagestan in January 2012, he probably would have been under scrutiny throughout his time there.

“He would have been flagged at the airport, when he entered Dagestan and when he went to the mosque,” said Jean-Francois Ratelle, a Canadian scholar at George Washington University who is studying the insurgency in Dagestan.

Ratelle said that in his own research trips to Dagestan, he had been stopped almost every day on the street by police officers checking his registration papers, in part because his beard is seen as a possible sign of religious devotion.

It is unclear how closely the police were tracking Tsarnaev, but his mother described at least one instance in which her son was stopped by the police along the beach in Makhachkala, where Tsarnaev’s parents live, and brought in for questioning.

“He’s like: ‘The police came there and they asked for documents,’” Tsarnaeva said at a news conference last week. “They asked him to follow. He was asking them, he was like in shock. He’s like: ‘What, is there something wrong with me? Am I strange, or don’t look like everybody?’”

At the news conference, the brothers’ father, Anzor Tsarnaev, acknowledged that Tamerlan had occasionally prayed at a mosque on Kotrova Street in Makhachkala that is known as a gathering spot for Salafists with extremist views. The mosque is just a short walk from the soccer stadium for the local Dynamo team. Graffiti, written in stark red on a white wall nearby the mosque says, “Victory or paradise.”

In an interview, the imam at the Kotrova Street mosque, Khasan-Khadzhi Gasanaliev, said he had never met Tamerlan Tsarnaev, and none of the men interviewed outside the mosque over the course of several visits said they had known him.

Videos posted by Tamerlan Tsarnaev indicate that he was familiar with Muslim rebel leaders in Dagestan, and investigators have been seeking to determine if he met with any of them in person.

The account in Novaya Gazeta said that one of Tsarnaev’s contacts was Mahmoud Mansur Nidal, who was killed May 19 after a standoff with Russian authorities at an apartment house in Makhachkala. Surrounded by Russian security forces, Nidal took several hostages, according to the news agency Interfax, and at one point threw a grenade at the authorities. The hostages were released after some negotiation, but Nidal refused to surrender and was shot dead, Interfax reported.

Another possible contact was Plotnikov, a Russian emigre to Canada who became disenchanted with life there, converted to Islam and then moved to Dagestan to join the Muslim insurgency. He had been trained in boxing by a well-known Russian coach in Canada and was known among the Muslim rebels in Dagestan as “The Canadian.”

Plotnikov became a member of the Mujahideen of the Caucasus Emirate and had briefly been detained by Russian authorities.

Law enforcement officials have said that the marathon bombs were constructed largely according to instructions in Inspire magazine, a publication of the al-Qaida branch in Yemen. But Rep. Michael McCaul, R-Texas and chairman of the House Homeland Security Committee, said on “Fox News Sunday” that “the level of sophistication” of the homemade pressure-cooker bombs used at the marathon “leads me to believe that there was a trainer.”