Explosions at the Boston Marathon finish line have been reported widely on Twitter and captured on video, as photographers catalog a disaster whose cause is still unknown. According to the Associated Press, two explosions rocked the finish line, and Boston's Police Department initially said that 23 are injured and two dead after briefly reporting 22 injured. Later in the day, that number rose to 64 injured and at least two dead, and it was set at 90 injured and two dead as of 5:45pm ET.

Now, the number continues to climb, with CNN reporting on television that 110 have been injured, Boston.com reporting 115, and ABC reporting 99. As of 8:50pm ET, the Boston Police Department says that three have died. Police broadcasts indicate that law enforcement is looking for potential explosive devices. The area is being evacuated and locked down, with the victims moved from the scene; emergency teams have urged others to tell people about the evacuation. Many of the people who arrived to document the end of the race captured powerful photographs of the event, some of which are published at The Atlantic.

Reuters reports that there is still "no indication" of how many people have been injured. The Boston Police have confirmed the explosion "with injuries," however, though there's still no word on a cause.

Update: In response to the explosions, New York police are also apparently stepping up their security: Reuters reports that the NYPD is deploying counter-terrorism vehicles around landmarks and hotels. In Boston, the Lenox Hotel was reported evacuated, and the Mandarin Hotel was reported as the possible site of an explosive device. According to Boston.com, the police have found "secondary devices" that are still unexploded, urging anyone in the area to leave.

Police are now attempting a controlled explosion of one of the remaining bombs

The marathon has been officially canceled, with the Boston Marathon reporting that the explosions were from bombs: "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." Police are now attempting a controlled explosion of one of the remaining devices that they've found. All off-duty officers have been ordered to respond and help. Cellphone networks are reportedly down.

Update: While we've seen countless real reports on Twitter, there's also clearly some misinformation: an apparently fake Boston Marathon account is promising to donate money based on retweets. Officially, a press conference has been called: the Boston Fire Department has tweeted that it will be held at 4:30pm ET at the Westin Hotel.

Media Briefing Marathon 4:30pm Westin Hotel 3rd floor Essex South meeting room — Boston Fire Dept. (@BostonFire) April 15, 2013

Boston's Police Department is also posting periodic updates: it's just confirmed that 23 were injured and two people are dead, and police scanner reports indicate that more "suspicious packages" are being found. The NYPD, meanwhile, has officially said it is "stepping up security" until more is known about the situation. A White House official has said that Obama is aware of the situation and in contact with local authorities to provide assistance. Joe Biden, meanwhile, has said that "our prayers are with those people in Boston" at the end of a press conference on gun control.

Update: NBC News reports that officials say a "small homemade bomb" is potentially the cause of the explosion, and Boston public services continue to be on alert: part of the Green Line has been suspended, and police are sweeping for more devices. The AP reports that "two more explosive devices" were found and deactivated at the Boston Marathon.

Update 4:37pm ET: ABC is quoting police as urging bystanders not to use cellphones around the site of the Marathon, as it "could set off other devices."

Police telling people on scene of Boston Marathon #explosions to not use cell phones because could set off other devices — ABC News (@ABC) April 15, 2013

Update 4:43pm ET: CBS television news has reported that police have surveillance video of a possible suspect bringing backpacks into the area, though this has not been confirmed officially.

Update 4:46pm ET: Since the explosion, police and others have periodically reported a possible other incident at JFK Library. While photographs have shown an apparently burned-out building, JFK Library has said that the incident was a result of a fire in the mechanical room, and there's currently no clear connection to the explosions. The fire is now out, with all staff and visitors "accounted for and safe."

Update 4:52pm ET: A press conference has just begun, with Police Commissioner Ed Davis reporting two explosions at approximately 2:50pm, each with "multiple casualties." Davis has also called the JFK Library incident an "explosion;" though he has said it's not confirmed that the incidents are connected, the police are treating them as if they were. Police are asking anyone with information about the explosions to call 1-800-494-TIPS. The FBI and National Guard have both been deployed to help police with the investigation. People in the area are being diverted away from the area, and Davis urged anyone in the area to stay at home and avoid being in groups. Police are currently checking all packages left behind at the site in case of more possible explosive devices.

Update 5:07pm ET: While we've heard before about cellphone service being unavailable, the AP is now reporting that it has been shut down across Boston. Meanwhile, the Red Cross is urging people to use either social media or its Safe and Well tool to get in touch with friends and family. Google has also created its own tool for finding people at the Boston Marathon explosions.

Update 5:24pm ET: The official Boston Police Twitter account is now saying the JFK Library incident is currently believed to be "fire related," though it's possible that judgment will change at a later point. NBC has said that Boston police are guarding a "possible suspect" at the hospital.

Update 5:58pm ET: President Barack Obama is set to speak at around 6:10pm ET about the explosions; we'll be covering as soon as it starts. Boston's mayor is now holding another press conference, and the JFK Library fire is now described as being due to an "incendiary device" or a fire, continuing to be a point of uncertainty although it's currently said to be "unrelated." For now, the AP has also doubled back on its story about cell networks being shut down, saying that some remain functional.

"There is no suspect in custody."

Commissioner Davis has contradicted earlier news, saying that while people are being questioned, no one is in custody. "Those reports are not true," he says. "There is no suspect in custody. we're questioning many people, but there is no suspect in custody." Davis declined to state how many people had been killed in the explosion, though he confirmed once again that there were casualties.

Update 6:13pm ET: President Obama is now speaking, saying that the country will "say a prayer for the people of Boston" but that he still does not know who was responsible. "We will find out who did this, and we will hold them accountable," he says. "Any responsible groups will feel the full weight of justice." He has also urged people not to jump to conclusions before all the facts had been reported.

Update 6:43pm ET: In the latest update from the Boston Police Twitter feed, Commissioner Davis says that the JFK Library incident "may not have been an explosion. It may have been a fire." We're also now seeing multiple news agencies calling the explosions "terrorism," though that's not meant to indicate a connection with al-Qaeda despite the association. Bloomberg quotes an unnamed White House official who also calls it an "act of terror."

White House official: "Any event with multiple explosive devices - as this appears to be - is clearly an act of terror." — Bloomberg News (@BloombergNews) April 15, 2013

ABC has also reported a couple of new details, including that the injury toll is 78, with 8 previously reported cases actually injuries from the race. That is contradicted by CNN, which is currently reporting on television that the injury toll is 110. An 8-year-old boy is reported by NBC to be among the deceased. ABC also reports that the devices were triggered by remote detonation, something that was widely speculated on earlier today.

Update 8:31pm ET: Fox News and CNN are both reporting that the bombs used ball bearings as shrapnel, which suggests they were designed to injure people rather than simply make a statement. Hospitals are "pulling ball bearings out of people in the emergency room," according to a "terrorism expert" who spoke to CNN.

Update 8:39pm ET: The Wall Street Journal reports that officials found a total of five undetonated explosive devices "around the Boston area."

Update 8:50pm ET: The FBI has taken charge of the ongoing investigation, as of a press conference this evening. Massachusetts governor Deval Patrick announced the handover, adding that things will not be "business as usual" in Boston tomorrow: among other things, riders of public transportation can expect random checks of their backpacks and other parcels. Police commissioner Ed Davis reasserted that there is currently no suspect in the case, and that while the Boylston street area has been nearly cleared of potential bomb locations, the department is getting an ongoing influx of tips about suspicious packages in other areas. The death toll has risen to three.

Update 9:35pm ET: The Wall Street Journal has now updated its story, reporting that after closer examination investigators "doubt" that the five additional devices found were in fact bombs.

Update 10:04pm ET: A doctor from Massachusetts General Hospital just gave some additional details on what he's seen today. According to trauma surgeon Peter J. Fagenholz, the hospital has treated 29 individuals, and doctors have performed several amputations over the course of the day. Eight of the patients at Massachusetts General remain in critical condition. While they are noticing lots of metal debris when treating patients, Fagenholz said "I don't think we're able to say if these were placed there intentionally [in the explosive device] or if they're small bits of metal from the scene."

Doctors at Massachusetts General have seen at least one case of shattered eardrums, and treated one patient over the age of 71 — though they did not treat any minors. The majority of the injuries that they've seen have hit the lower extremities, but despite the grim nature of the incident today Fagenholz said "the injuries are not otherworldly."

When asked how the patients were expected to recover, Fagenholz told reporters that "It's really too early to say how everyone is going to do," but that "a number of patients will require repeat operations tomorrow." The doctor noted that the trauma ward is no stranger to extreme injuries, "it's just depressing that it's intentional."

Update 11:24pm ET: People in and around Boston have been putting their names and numbers into a spreadsheet offering their homes for anybody who needs a place to stay, created by Boston.com.





Here are a few of the immediate reactions from the event and its aftermath.

Warning: Graphic imagery below