Explosions At The Boston Marathon; 3 Dead, Scores InjuredS

Minutes after two bombs exploded near the finish line of the Boston Marathon at 2:50 p.m., reports started rolling in. We began this post soon after, with chronological updates continuing through the evening. Some photos might be graphic.

This photo, showing the immediate aftermath, is from Twitter user @theoriginalwak.

Explosions At The Boston Marathon; 3 Dead, Scores InjuredS

A Boston Globe staffer says dozens have been injured. The media hotel is on lockdown.

Photo from Twitter user @Boston_to_a_T:

Explosions At The Boston Marathon; 3 Dead, Scores InjuredS

CBS Boston has live video of the finish line area. And here's the Boston EMS live feed.

Some of CBS Boston's coverage of the aftermath:

Explosions At The Boston Marathon; 3 Dead, Scores Injured

(Video removed by request of CBS. View it here.)

Another photo, from a Globe Staffer on the scene:

Explosions At The Boston Marathon; 3 Dead, Scores InjuredS

Via Jackie Bruno of NECN:

Explosions At The Boston Marathon; 3 Dead, Scores InjuredS

Via @brm90:

Explosions At The Boston Marathon; 3 Dead, Scores InjuredS

Via Matt Norlander, a screengrab from CBS's broadcast apparently showing an explosion.

Explosions At The Boston Marathon; 3 Dead, Scores InjuredS

Via Matt Perrault, smoke rising over the Boston skyline:

Explosions At The Boston Marathon; 3 Dead, Scores InjuredS

From Globe photographer David Ryan:

Explosions At The Boston Marathon; 3 Dead, Scores InjuredS

Via the police scanner, the marathon is canceled. Anyone still on the course should stay away from Boylston Street or Copley Square.

Video of an explosion near the finish line:

Ground-level video of the explosion, with audio. You can see and hear the second explosion at the 10-second mark:

Cell phone video, at a distance, of the second explosion:

The marathon was being run in honor of the victims of the Newtown massacre. Some families were apparently watching from near the finish line:

For those looking for information on specific runners, the marathon has a chip-based tracking system. You can consult it here.

Around 3:55, the bomb squad set off a controlled explosion opposite the library.

The marathon organizers have released a brief statement:

There were two bombs that exploded near the finish line in today's Boston Marathon. We are working with law enforcement to understand what exactly has happened.

An Associated Press photo of Boston police, fire, and EMS services swarming the scene:

Explosions At The Boston Marathon; 3 Dead, Scores InjuredS

Boston Police in the immediate aftermath, from Globe photographer John Tlumacki:

Explosions At The Boston Marathon; 3 Dead, Scores InjuredS

From Boston PD's public information chief:

Raw video of the immediate response, from the Boston Globe.

The New York Times has a graphic showing the locations of the two explosions, about a block apart on Boylston St.

An official tells the AP that additional devices were located, in addition to the two that exploded. It's not known if this includes the one detonated by the bomb squad.

Possibly related, at 4:27 the scanner reported a confirmed explosion at the JFK library, with no injuries reported.

If you're running, or looking for a runner, the meeting area has been changed:

Tonight's Senators-Bruins game is reportedly off:

Intense video of the first explosion, from Steve Silva, Boston.com producer:

Boston PD commissioner Ed Davis confirms there was a third incident at the JFK Library, several miles from Copley Square. There were no injuries. (A library spokesperson says it was a fire in the mechanical room.)

An official tells the AP that cell phone service in downtown Boston has been shut off or limited to prevent detonations of any undiscovered devices. (Update: this was apparently a false report.)

From Getty, a bomb squad member investigates an item near Kenmore Square:

Explosions At The Boston Marathon; 3 Dead, Scores InjuredS

From the AP, a spectator tries to find a friend after the marathon was canceled:

Explosions At The Boston Marathon; 3 Dead, Scores InjuredS

Via Eric Twardzik, a photo taken around 5:30 of a man being handcuffed on the Boston Common. Twardzik says he's wearing a white baseball cap:

Explosions At The Boston Marathon; 3 Dead, Scores InjuredS

In a 6:00 press conference, the police commissioner says the fire at the JFK library appears to be unrelated to the marathon blasts.

The Post has been reporting that a potential suspect is under guard at a Boston hospital, citing "federal officials." Police Commissioner Davis seemed to dismiss that, saying BPD had no one in custody. NBC News now reports on a "possible suspect" who was injured in the blast. It's worth noting that neither the Post nor NBC had claimed anyone was arrested.

The latest casualty figures:

MBTA Green, Red, and Orange Line service has resumed, though riders can expect delays.

President Obama's statement on the bombings:

The Globe has a graphic showing the blast sites on the marathon route.

A stunning Globe photo of marathoners being stopped at Massachusetts and Commonwealth, about a half-mile from the finish:

Explosions At The Boston Marathon; 3 Dead, Scores InjuredS

Here's a list of Bostonians offering up a place to stay for the night. It's a long list.

This post is no longer being updated. Check the front page for further developments.