BOSTON, Massachusetts (UPDATED) - Dzhokhar and Tamerlan Tsarnaev, suspected of bombing the Boston marathon, appear to hail from Russia's war-torn Chechnya but had been in the United States for several years.
The North Caucasus region of Chechnya has been ravaged by two back-to-back wars since 1994 between Russia's army and increasingly Islamist-leaning separatist rebels, and the mountainous region still sees occasional fighting.
A US law enforcement official would only say on condition of anonymity that the two brothers were Russian, but online profiles with pictures strongly resembling their wanted posters describe them as Muslim refugees.
NBC News reported that they hail from Chechnya, but they appear to have left during the wars and spent time in Central Asia.
Dzhokhar, a baby-faced 19-year-old still at large, won a scholarship in 2011 while enrolled at the Cambridge Rindge and Latin School, a public high school. He was also named a Greater Boston League Winter All Star wrestler that year.
In a profile on a Russian-language site similar to Facebook, he says he speaks Chechen. The site says that Dzhokhar identifies "Islam" as his world view, and "career and money" as his main goals in life.
It also lists information about Chechnya and Islam as well as different mosques around the world, and retells some jokes about the unfair treatment of Muslims in the North Caucasus.
One of the jokes reads: "They have this riddle in school. There is a car. Inside are a man from Dagestan, a second man from Chechnya and a third man from Ingushetia. Question -- who is driving the car? Answer -- the police."
'There are no values anymore'
Tamerlan, 26 -- who was killed during the police chase -- 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, a gym mentioned in an online profile in his name.
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 left because of the conflict in the 1990s and spent years in Kazakhstan before coming to the United States as a refugee.
But Ruslan Tsarni, identified by CNN as the boys' uncle, said in an interview broadcast by the network that they grew up in Kyrgyzstan, a former Soviet Central Asian republic.
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!"
"In my opinion, my children were set up by the secret services because they are practising Muslims," Anzor Tsarnaev told the Interfax news agency from the North Caucasus Russian city of Makhachkala.
Anzor Tsarnaev is the father of 26-year-old Tamerlan Tsarnaev, who was shot dead by police in Boston, and his 19-year-old brother and co-suspect Dzhokhar, who remains on the run in the area, Interfax said.
"Why did they kill Tamerlan? They should have taken him alive," said the father.
He added that the younger brother Dzhokhar "is in hiding. He was a second-year student in a medical university. We were waiting for him to come back (to Russia) for the holidays."
"Now I do not know what will happen," he said. -Mariano Andrade, Agence France-Presse/Rappler.com