Boston marathon bomber Dzhokhar Tsarnaev spent the two days following his terrorist attack following his normal student routine- and even attending a party, it has emerged.
Just hours after killing three and injuring 170 using improvised nail bombs, Dzhokhar Tweeted “Ain’t no love in the heart of the city, stay safe people,” a reference to a Jay-Z lyric.
The 19-year-old even attended a football party two days later at the University of Massachusetts-Dartmouth where he was studying towards a medical degree. An unnamed woman who was at the event said he seemed “relaxed” and he himself Tweeted: “I’m a stress-free kind of guy.’’
As the full resources of the FBI and Boston police were dedicated to finding him, Tsarnaev continued sleeping in his student dormitory and going to the gym.
It was not until the authorities released clear pictures of Dzhokhar and his brother and co-conspirator, Tamerlan, 26, that the pair decided to break cover, shooting dead an MIT campus policeman Sean Collier.
There followed a dramatic car chase during which the Tsarnaevs carjacked an SUV, taking its driver hostage, and threw home-made bombs at pursuing police.
Dzohokhar was wounded but managed to escape and hide himself in a boat stored in a garden as police conducted almost 20 hours of door-to-door searches. He was finally captured following a shootout.
His brother died in the initial shootout. The mother of Tamerlan’s wife, Katherine, with whom he had a daughter, said today the family “could not comprehend” what had happened and realised they had “never really known” him.
The pair met at Suffolk University in Boston and shortly afterwards Katherine Russell, as she was then, converted to Islam.
Father: Dzhokhar is an 'intelligent' medical student
Dzhokhar was a member of the class of 2011 at Cambridge Rindge and Latin School, graduating that year.
And he won a $2,500 scholarship from the city of Cambridge, Massachusetts, to pursue higher education.
Speaking about Dzhokhar, his father Anzor Tsarnaev said: “My son is a true angel.”
He added: “Dzhokhar is a second-year medical student in the U.S. He is such an intelligent boy. We expected him to come on holidays here.”
The elder Tsarnaev spoke by telephone from the Russian city of Makhachkala with the Associated Press news agency on Friday.
His surviving son was born in Kyrgyzstan and had a Massachusetts driver's licence, according to law enforcement officials quoted by NBC News, while Tamerlan was born in Russia.
Dzhokhar was reportedly an all-star wrestler and a student at the University of Massachusetts Dartmouth.
He also worked as a lifeguard at Harvard University, one former pupil of Rindge & Latin told CNN.
Dzhokhar was 'normal', says classmate
Lulu Emmons, who went to Rindge & Latin - the city's public high school - with Dzhokhar.
"He was normal," she said.
“He kind of fit in with everyone. Not really close with anyone, but he was friendly.
“I am just a little shocked. I sat next to this guy. I joked with him. I laughed with him. I had class with him. It is a little crazy,” she said.
Former teacher and school photographer Larry Aaronson also knew Dzhokhar, reported the Boston Globe website.
He said: “If someone were to ask me what the kid was like, I would say he had a heart of gold. He was as gracious as possible.”
He said that Dzhokhar had conversations about the fact the youngster came from a war zone.
The younger brother reportedly attended School No. 1 in Makhachkala, the capital of Dagestan, before moving to the US.
Dzhokhar Tsarnaev's page on the Russian social networking site Vkontakte sees him describe himself as speaking Chechen as well as English and Russian. His world view is described as "Islam" and he says his personal goal is "career and money".
He became a US citizen on September 11, 2012, according to a federal official, reported CNN.
Tamerlan: a boxer with hopes of joining US Olympic team
As an amateur boxer, he was listed as a competitor in a National Golden Gloves competition in 2009.
The same report highlighted a photo essay about Tamerlan’s love of boxing that suggested all was not right for him in his adopted country.
“I don’t have a single American friend," he said, in a photo caption.
“I don’t understand them.”
Tamerlan studied at Bunker Hill Community College and wanted to become an engineer.
But he took a semester off from the college, in Boston, to train for a big competition - telling the photographer that he hopes to win enough fights to be selected for the US team and be a naturalised American.
The would-be Olympian also said he would rather compete for the US rather than for Russia unless Chechnya becomes independent, reported the BBC.
He also reportedly said to being "very religious", and that he did not smoke or drink anymore.
The BBC report also highlighted information from a Russian news agency about "extremist material" was on the YouTube account belonging to Tamerlan - with one album titled "terrorist".
But the BBC said it was unable to confirm the presence of such material on Tamerlan's YouTube page.
According to the website spotcrime.com, Tamerlan was arrested for domestic violence in July 2009, after assaulting his girlfriend.
In 2011, he was interviewed by the FBI following a tip-off from a foreign intelligence agency.
The brothers' journey to the US
Tamerlan's photo essay said that the family left the Russian republic of Dagestan - a predominantly Muslim region on the eastern border of Chechnya -- and lived in Kazakhstan for years before arriving in the US as refugees, according to the Boston Globe website.
It also quoted the state news agency of Kyrgyzstan as saying the brothers are ethnic Chechens who lived in the central Asian country until “roughly 2001,” when they moved to Dagestan.
An official in Kyrgyzstan told CNN that the brothers were Kryrgyz passport holders and used those passports when applying for green cards in the US.
Many fleeing from the Caucasus conflict were given passports or refugee status in neighbouring countries.
The headmaster of a school in Dagestan that was attended by members of the family - comprised of two brothers and two sisters - was also quoted in the CNN report as saying they arrived in 2001 as refugees from Kyrgyzstan.
The suspects' uncle, Ruslan Tsarni of Montgomery Village, Maryland in the US, said the men lived together near Boston and have been in the US for about a decade.
They lived in the Massachusetts town of Cambridge, which is home to Harvard University.