Boston marathon bombing suspects Dzhokhar and Tamerlan Tsarnaev are Muslims of Chechen origin whose social media pages express sympathy with the struggles of their homeland.
Dzhokhar, a baby-faced 19-year-old still at large, was an all-star high school wrestler described as hard-working and kind. Tamerlan, a 26-year-old killed in a shootout, was an engineering student who loved boxing.
"He was a lovely, lovely kid," Larry Aaronson, a neighbor, told CNN when asked about Dzhokhar, expressing shock that he could have been involved in Monday's double bombing, which killed three people and maimed scores more.
"You get people that say, 'Oh, I know him. He's not capable of this.' That's what I'm saying to you. I am just one of those people."
A page on the VKontakte social media website, Russia's equivalent to Facebook, says Dzhokhar went to elementary school in the Dagestani city of Makhachkala in southern Russia from 1999-2001.
Dagestan borders the North Caucasus region of Chechnya, which has been ravaged by two back-to-back wars since 1994 between Russia's army and increasingly Islamist-leaning separatist rebels.
The Tsarnaev family appears to have left the volatile Caucasus region, which still sees occasional fighting, during the wars and subsequently spent time in Central Asia.
"We're Muslims, we're Chechens, we're ethnic Chechens," Ruslan Tsarni, who said he was the uncle of the suspects, told US media.
"Somebody radicalized them. It's not my brother."
The VKontakte page says that Dzhokhar graduated in 2011 from Cambridge Rindge and Latin School, a public high school, identifies "Islam" as his world view, and "career and money" as his main goals in life.
It also lists information about Chechnya and Islam, and relates jokes about the unfair treatment of Muslims in the Caucasus region.
"They have this riddle in school. There is a car. Inside are a man from Dagestan, one from Chechnya and another from Ingushetia... Who is driving the car? The police," it says.
The 26-year-old Tamerlan appears to have been featured in an online photo essay by Johannes Hirn entitled "Will Box for Passport," in which he says he has been living in America for five years.
"I don't have a single American friend, I don't understand them," he is quoted as saying under one of several pictures of him boxing at the Wai Kru Mixed Martial Arts Center.
The website says Tamerlan, who was studying engineering at Bunker Hill Community College, had taken a year off to train for the National Golden Gloves competition in Salt Lake City, Utah.
It says he is originally from Chechnya but fled the conflict in the 1990s and spent years in Kazakhstan before coming to the United States as a refugee.
On the website, Tamerlan is quoted as saying he aspires to be an Olympic boxer, but would rather compete for the United States than for Russia in the absence of an independent Chechnya.
He is quoted as describing himself as "very religious" and saying, "God said no alcohol."
"There are no values anymore," he is quoted as saying. "People can't control themselves."
But another caption says his favorite movie is "Borat," and one picture shows him with a blonde woman whom he describes as his half-Italian, half-Portuguese girlfriend, saying she converted to Islam.
"She's beautiful, man!" he says.
A YouTube account in his name created on August 17, 2012 linked to videos of a radical Australian preacher, Feiz Mohammad, and had a playlist entitled "terrorists," according to the Washington-based SITE Intelligence Group.
SITE said the videos in the playlist had been removed, but a saved page indicates they were related to Dagestan militants.
A man claiming to be the boys' father, Anzor Tsarnaev, speaking to Russia's Interfax news agency from Makhachkala, said his children "were set up by the secret services because they are practicing Muslims."
"Why did they kill Tamerlan? They should have taken him alive," he said.
He added that the younger brother Dzhokhar "is in hiding. (...) We were waiting for him to come back (to Russia) for the holidays."
"Now I do not know what will happen," he said.