The Federal Bureau of Investigation (FBI) on Thursday released pictures and video of two young men, who officials suspect to be responsible for the twin blasts at Boston Marathon that killed three people and injured more than 170 on Monday, officials said.
The images were made public in an attempt to seek direct help from the common men to arrest the suspects.
Special Agent in Charge Richard DesLauriers at a Press Conference said: "Our collective law enforcement team has pursued thousands leads and tips. As I said two days ago, we are working methodically and with a sense of urgency to identify those responsible for the bombings. Within the last day or so, through that careful process, we initially developed a single person of interest. Not knowing if the individual was acting alone or in concert with others, we obviously worked with extreme purpose to make that determination."
"More importantly, it was done to ensure the future safety of the city, the commonwealth and the country. Indeed, through that process, the FBI developed a second suspect. Today, we are enlisting the public's help to identify the two suspects," he said.
"After a very detailed analysis of photo, video, and other evidence, we are releasing photos of the two suspects. They are identified as Suspect 1 and Suspect 2. They appear to be associated," he said.
"Suspect 1 is wearing a black hat. Suspect 2 is wearing a white hat. Suspect 2 set down a back pack at the site of the second explosion just in front of the Forum Restaurant," DesLauriers said.
"We strongly encourage those who were at the Forum Restaurant who have not contacted us yet to do so," he said.
As you can see from one of the images, Suspects 1 and 2 appear to be walking together through the marathon crowd on Boylston Street in the direction of the finish line. That image was captured as they walked on Boylston in the vicinity of its intersection with Gloucester Street.
According to reports, the two men appear to be in their 20s. However, DesLauriers did not put across his opinion regarding their possible ethnicity or national origin.
"Somebody out there knows these individuals as friends, neighbors, co-workers, or family members of the suspects. Though it may be difficult, the nation is counting on those with information to come forward and provide it to us," he was quoted as saying on media.