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Manchester, New Hampshire (CNN) -- The trail of Boston Marathon bombing suspect Tamerlan Tsarnaev has led investigators to the New Hampshire home of a former Chechen rebel living in exile, a law enforcement official told CNN on Friday.
FBI agents interviewed Musa Khadjimuradov and searched his Manchester home this week, said the official, who spoke on condition of anonymity.
While the official did not detail what investigators uncovered during the search or the contents of the interview, Khadjimuradov indicated in an e-mailed statement to CNN that he was questioned about his contact with dead suspect Tamerlan Tsarnaev.
Authorities have cast a wide net in the investigation into the Boston bombings, examining everything from the suspects' movements to people they knew, to determine whether Tamerlan Tsarnaev or his younger brother, Dzhokhar Tsarnaev, received help in carrying out the attack.
"I am sure the FBI knows by now that I have nothing to do with the terrible act in Boston," Khadjimuradov said in the statement.
"I would like to state that I barely knew the Tsarnaev family, and only met them for the first time after we moved to the U.S. During the very few encounters, which were initiated by Tsarnaev, we have never discussed political or religious issues, so I could never guess what ideas were in their minds."
Khadjimuradov, 36, said this week was the second time he has been questioned by federal authorities about his relationship with the elder Tsarnaev, who visited his home about three weeks before the April 15 bombings that left three dead and hundreds wounded.
Investigators first talked to him on April 29, he said.
In an interview this week with Voice of America, Khadjimuradov said he believes federal investigators questioned him because they wanted to know whether Tsarnaev had used a shooting range in the area.
"Because they say he has shooting practice here in New Hampshire. That's like two or three times. So he bought fireworks here, from New Hampshire, you know? And he buy some ammunition for guns here in New Hampshire. And before the attack, like three or four weeks, he came to my house," he said.
"So now I believe they're thinking like he was coming here to New Hampshire and that I try to help him or something."
He told Voice of America that he met Tamerlan Tsarnaev at a Chechen Society gathering in Boston in 2006, he had seen him only three times in three years, and the discussions were never about religion or politics.
"Nothing. Never. He never talking about the religious, politics or anything like that to me," he said.
Authorities have said the surviving Tsarnaev brother told investigators that no one else was involved.
In addition to questions about how the bombings were carried out, investigators have been trying to determine how the Tsarnaev brothers were allegedly radicalized.
Authorities have said they believe the brothers acted alone, but are investigating whether they could have learned from or been aided by terror groups, including groups overseas.
The Tsarnaev brothers, ethnic Chechens, lived in Kyrgyzstan and Dagestan in Russia's volatile North Caucasus region, where Islamic insurgency has taken hold in a fight for independence.
Of particular interest has been Tamerlan's 2012 trip to the semi-autonomous Russian republic of Dagestan, home to numerous Islamic militant groups that have warred against Moscow's rule.
Russian authorities asked U.S. officials to investigate Tamerlan before the trip, saying they believed he was becoming increasingly involved with radical Islam. The FBI investigated, but found no evidence of extremist activity, FBI Director Robert Mueller told a Senate committee.
In his statement, Khadjimuradov said he understood why authorities wanted to talk to him and that he fully cooperated.
"These guys need to do everything they can to solve this case, so they can prevent anything like this horror from happening again," it said.
Khadjimuradov, who relocated to the United States in 2004 as a refugee, has said he served as one of the bodyguards for Akhmed Zakayev, a Chechen separatist leader wanted by Russia. Zakayev, who now lives in London, did not immediately respond to a CNN request for comment.
Khadjimuradov told Voice of America and The New York Times he was paralyzed after being shot in the back by Russian security forces in 2001.
CNN's Susan Candiotti contributed to this report.