“Whatever hateful agenda drove these young men to such heinous acts will not prevail,” Obama said. “Whatever they thought they could ultimately achieve, ultimately failed.”
Though the pursuit of the bombers began almost immediately after Monday’s bombings, it was not until the seemingly random murder of an MIT police officer Thursday night that law enforcement officials advanced the case, suid Massachusetts State Police Colonel Timothy P. Alben in an impromptu press conference convened shortly before 4:30 a.m. Friday and again at Friday night’s conference after Tsarnaev’s capture.
In a statement released early Friday morning, the Cambridge Police Department wrote that they first received a report around 10:20 p.m. Thursday that shots had been fired on the MIT campus. When they arrived on the scene at 10:30 p.m., CPD found an MIT officer, in his car, with multiple gunshot wounds. That officer, identified as 26-year-old Sean Collier, was transported to Massachusetts General Hospital, where he was declared dead on arrival, according to the Middlesex County District Attorney’s Office.
Cambridge police also received reports of an armed robbery at a 7-Eleven in Central Square at 10:30 p.m. Though that incident was initially thought to be related to the murder, Alben said Friday that law enforcement had determined the two were unrelated, but that the bombing suspects were in the store at roughly the time of the robbery.
Shortly thereafter, they said, an armed hijacking occurred around Third Street in Cambridge, when two male suspects held the owner of the car, a Mercedes SUV, at gunpoint. The car owner was released roughly half an hour later at a gas station off Memorial Drive.
When the stolen Mercedes was spotted in Watertown by police in that area, Alben said, a mass chase ensued as CPD, Massachusetts State Police, and the FBI joined the effort. It ultimately resulted in a firefight between law enforcement and the two suspects, who threw improvised explosive devices and homemade grenades and traded some 200 rounds of gun shots with law enforcement, Davis said.
“This is the stuff that in an urban police department, it’s almost unheard of,” Davis said Friday night after Tsarnaev’s capture.
In his haste to escape police, Tsarnaev drove over his older brother’s body, which was bound with explosives, law enforcement officials said.
In addition to Tamerlan Tsarnaev, and the MIT police officer, one MBTA Transit Police officer was shot in the gunfire exchange en route to Watertown Thursday night. That officer is in stable condition, MBTA officials said Friday.
Alben identified Dzhokhar Tsarnaev as the same man suspected of helping to carry out Monday’s bombing and seen wearing a white hat in surveillance video from the marathon. Officials believe Tamerlan Tsarnaev is the same man seen wearing a black hat and sunglasses in other surveillance video.
The Tsarnaev brothers immigrated to the United States a decade ago from Chechnya and lived in central Cambridge. Dzhokhar Tsarnaev attended Cambridge Rindge and Latin School and worked part-time as a lifeguard at Harvard’s Malkin Athletic Center, former classmates said Friday.
In response to the ongoing search for the alleged terrorist, the University closed all operations on Friday, advising students to stay inside as much as possible.
—Matthew Q. Clarida and Samuel Y. Weinstock contributed to the reporting of this story.
—Staff writer Nicholas P. Fandos can be reached at nicholasfandos@college.harvard.edu. Follow him on Twitter @npfandos.
—Staff writer Nikita Kansra can be reached at nikitakansra@college.harvard.edu. Follow her on Twitter @NikitaKansra.
This article has been revised to reflect the following correction:
CORRECTION: April 22, 2013
An earlier version of this article misquoted Boston Police Commissioner Edward F. Davis as describing the capture of the marathon bombing suspect as something “that an urban police department has never heard of.” In fact, Davis described the manhunt as something “that in an urban police department, it’s almost unheard of.”