The first explosion that rocked the Boston Marathon near the finish line on Monday. Photo: YouTube screenshot.

The FBI suspects two young men from a region in Russia close to Chechnya of involvement in the Boston Marathon bombings. Tamerlan Tsarnaev, 26, was killed after a shootout with police and officers are still actively searching for his brother Djohar Tsarnaev, 19. Police urged Boston residents to stay at home as they conduct a city-wide manhunt for Tsarnaev, and indicated he may be driving a gray Honda CRV, Massachusetts plate number 316 ES9, according the Associated Press.

A Massachusetts Institute of Technology police officer was fatally shot in a confrontation with the brothers Thursday, after which they stole a Mercedes SUV. Policed pursued the suspects and fired at them, at which point the suspects hurled several explosives back at police, some of which detonated. Police then shot the older brother while the younger brother fled. Tamerlan Tsarnaev later died at the hospital.

Djohar Tsarnaev was apparently studying at the Cambridge Ringe & Latin School, having settled in the U.S. as a refugee with his brother in 2001, the uncle of the two men, Ruslan Tsarni, told the Associated Press. He also said the older brother, Tamerlan, was a “loser” and “absolutely deserved his. They do not deserve to live on this earth.”

On his social media page of a Facebook-like site, VK, Djohar Tsarnaev listed himself as Muslim and listed his priorities as “career and money.” He belonged to several Muslim and Chechen pages and groups and posted links to Islamic websites with titles such as “Salamworld, my religion is Islam” and “There is no God but Allah, let that ring out in our hearts.” Tsarnaev posted videos of fighters in the Syrian civil war, a Reuters analysis revealed, as well as links to pages calling for the independence of Chechnya.

One of his last posts March 19 was a joke: “A car goes by with a Chechen, a Dagestani and an Ingush inside. Question: who is driving? Answer: the police.” He last logged on to the site Friday at 5:04 am. Russian and English abusive comments have appeared on his page since police identified him as a suspect in the bombing.