It began on the afternoon of April 15, when the Boston Marathon was attacked.
A beautiful day turned to scenes of terror.
And while people ran for their lives...
Many ran directly toward the danger.
This strange, wonderful breed of people just needed to help. They valued other people's lives over their own.
This spirit of love and devotion to the lives of strangers was never more apparent than in Carlos Arredondo.
But when the bombs went off, Carlos ran to do what he could, which, it turned out, was a lot. He was able to help save 27-year-old Jeff Bauman by closing his femoral artery to stem the bleeding. A moment that was captured in an instantly iconic photo.
On Thursday, the FBI, in turn, released photos of the two men...
As well as short security video clips.
The FBI was, in effect, asking the country to keep an eye out for these guys. Little did anyone suspect they would make themselves known again in short order.
Very late Thursday night, the suspected bombers allegedly robbed a convenience store. This would be the beginning of one of the longest nights in Boston history.
Shortly thereafter, a shooting occurred on MIT's campus, killing an MIT officer. The suspects had reportedly reemerged.
MIT identified the officer killed in the line of duty Thursday night as 26-year-old Patrol Officer Sean A. Collier.
As police were responding to reports of the shooting, they received notice of an armed carjacking of a Mercedes SUV near the campus. The two suspects had commandeered the car, eventually releasing its driver unharmed. The police chased the car through the city, and the pursuit came to a head in a small community called Watertown.
Several explosive devices were thrown from the car at the chasing police officers. Residents of Watertown were warned to stay in their homes.
Police exchanged gunfire with the suspects on the streets of this small town.
This is Richard Donohue, the transit officer wounded in the gun battle with the suspected bombers.
Suspect 1 was taken into custody during the firefight but died of gunshot wounds.
Suspect 2, however, escaped on foot, and is, according to police, armed and dangerous.
Here's a photo from Tsarnaev's VK.com account.
Authorities locked down the city. A perimeter around a section of Watertown was established.
The MBTA was shut down and repurposed to bring in more SWAT officers.
The plan? To go door-to-door until they find Tsarnaev. That kind of hunt looks something like this.
Swat teams went door-to-door, helping families evacuate their homes.
Streets around Boston remained empty during rush hour as police urged everyone in the area to remain in their homes.
More pictures surfaced of Dzhokhar Tsarnaev, the 19-year-old suspect who remains at large.
SWAT officers move from door to door in Watertown searching for the second bombing suspect.
The suspects’ uncle, Ruslan Tsarni, says "Of course we're ashamed" and pleads with his nephew to "Turn yourself in and ask forgiveness from the victims.”
Syrians send their condolences to the people of Boston.
On Friday afternoon, family members of the accused suspects expressed doubt that the brothers Tsarnaev could have been involved in this. First their aunt:
And then their father.
Their father's statement in particular was heartbreaking. It's impossible to imagine the anguish that would come from learning that your kids have possibly committed this kind of act.