As the world hunted him , the younger brother suspected in the Boston Marathon bombings acted like any other college sophomore . Dzhokhar Tsarnaev , 19 , was on the campus of University of Massachusetts-Dartmouth every day after the attack until late Thursday , a university official told CNN . Tsarnaev attended classes and dorm parties and went to the gym while the rest of Boston came to a tense standstill . A student at the school told The Boston Globe that she saw Tsarnaev at a party Wednesday night that was attended by some of his friends from intramural soccer . `` He was just relaxed , '' she said , asking the paper not to print her name . Another UMass Dartmouth student said he talked about the bombing with Tsarnaev for several minutes Tuesday while they were working out at the gym . Tsarnaev seemed normal , perhaps a little tired , Zach Bettencourt told CNN . Bettencourt said he told Tsarnaev something about the bombing , to the effect of , `` You hear about this kind of thing happening in Iraq and Afghanistan , but not here . '' `` He was like , 'Yeah , tragedies happen like this all the time and it 's sad , ' `` Bettencourt said , adding he had no inkling about anything suspicious with Tsarnaev , whom he described as a nice guy . The days-long drama that gripped Boston -- and the world -- began when two homemade bombs made from pressure cookers exploded 12 seconds apart near the finish line of Monday 's Boston Marathon . Three people were killed , and more than 170 wounded as nails , ball bearings , BBs and shards of broken glass were blasted through the viewing area . Law enforcement officials combed through photos and surveillance videos , searching for clues to who detonated the bombs . The FBI released photos showing two men they were seeking and asked for the public 's help . Suspects : Immigrant dream to American nightmare . At the dorm where Tsarnaev lived , students joked Thursday as they viewed the FBI photos on television , a senior who lived in the suspect 's dorm told The Boston Globe . `` We made a joke like , that could be Dzhokhar , '' said Pamala Rolon . `` But then we thought it just could n't be him . Dzhokhar ? Never . '' A tense scene began to unfold Thursday night -- complete with wailing sirens , flashes of blue and red lights , a hail of bullets and explosions from homemade bombs . By early Friday morning , Tsarnaev 's older brother , Tamerlan , 26 , was dead . Dzhokhar Tsarnaev was bleeding as he stole away into the night . On campus nobody was joking . The school posted a message on its website : `` UMass Dartmouth has learned that a person being sought in connection with the Boston Marathon bombing has been identified as a student registered at UMass Dartmouth . The campus is closed . Individuals on campus should shelter in place unless instructed otherwise . '' Older suspect grew increasingly religious , analysis shows . The manhunt for Dzhokhar Tsarnaev lasted all day Friday and left Boston streets deserted as police asked everyone to stay indoors . Then after the request was lifted , authorities got a tip : A Watertown man told police someone was hiding in his boat in the backyard , bleeding . It was their suspect , Watertown police Chief Edward Deveau said . Officers spotted Tsarnaev poking through the tarp covering the boat , and a shootout erupted , Deveau said . Police used `` flash-bangs , '' devices meant to stun people with a loud noise , and negotiated with Tsarnaev for about half an hour . Chief describes how manhunt ended . `` We used a robot to pull the tarp off the boat , '' David Procopio of the Massachusetts State Police said . `` We were also watching him with a thermal imaging camera in our helicopter . He was weakened by blood loss -- injured last night , most likely . '' A thermal image photograph , released Saturday by the state police , showed what authorities say was Tsarnaev lying in the middle of the boat . Police had no idea whether he had weapons or explosives with him , so they repeatedly told him to stand up and lift his shirt to show he was n't wearing a device , Deveau said . Eventually Tsarnaev stood up and lifted his shirt for the officers . `` Once we saw that , we felt comfortable enough to send some officer tactical equipment to grab him and pull him away from the boat , '' Deveau said . He was taken by ambulance to a hospital . Police are confident there are no other suspects , Deveau said . `` These two acted together and alone , '' he said . `` As far as this little cell and this little group , I think we got our guys . '' What their family has to say .
Dzhokhar Tsarnaev was seen on campus , at party after marathon bombings . Younger brother was found hiding in boat after manhunt . Authorities sought brothers after analyzing photos from scene . Older brother died in shootout , was run over by Tsarnaev , police say .