I saw many in my Twitter feed objecting to the terrorism/not terrorism debate today. While I can understand objecting to political posturing and sniping based on semantics, the terrorism designation has real legal meaning and news value. This investigation has been handed over to the FBI:

The Federal Bureau of Investigation has taken control of the investigation into the blasts, officials announced Monday night at a joint press conference between local, state, and federal authorities.

Though President Obama did not use the word “terrorism” in his address, which came just hours after the attack, White House officials have called it an “act of terror,” and the FBI’s presence is an indication it’s leaning that way:

Authorities said Monday evening that although the city would be operational Tuesday, ”there will be a heightened law enforcement presence,” according to Gov. Deval Patrick.

“It will not be business as usual” tomorrow in Boston, Patrick said.

The Boston Police Department has said that no arrests have yet been made and there are no suspects in custody. Davis emphasized that despite some media reports, there is no suspect at Brigham and Women’s Hospital.

FBI officials said Monday night that the investigation is a “criminal investigation that is a potential terrorism investigation.”

White House officials have said the bombing is being approached as “an act of terror.”

Update: The injury reports are grim, and the loss of three lives devastating, but after hearing reports of multiple other explosive devices found before detonation, and imagining the sheer number of people in their path, I shudder to think how much worse it could have been. We can also give some thanks that Boston has such world-class medical facilities close by. One of the deceased is an 8-year-old boy, and Boston Children’s Hospital offered a heartbreaking list of its young patients:

The dead included an 8-year-old boy, according to two law enforcement sources briefed on the investigation. Boston Children’s Hospital reported that those treated there included a 9-year-old girl, a 7-year-old boy, a 12-year-old, and a 2-year-old.

The Boston Globe has the total number of injured rising to 140 tonight:

Update: You may have heard quite a lot about a fire or explosion at JFK Library today, that was possibly related to the explosions. Initial reports were hazy on whether it was a fire or an explosion, and whether it was related. At an afternoon press conference, a Boston Police Department official seemed to confirm it was related, calling it a “third incident,” but here is the final version of the story. It looks like it may have been an electrical issue at a very bad time, but it’s still under investigation:

The JFK Presidential Library and Museum was evacuated this afternoon after a fire and a possible explosion that are being investigated for links to the blasts near the Boston Marathon finish line.

Tom Putnam, director of the library said the problem there appeared to be a mechanical fire that had nothing to do with the Back Bay bombings. As a precaution, police bomb squads performed a sweep of the Dorchester complex, he said.

Police Chief Edward F. Davis had said a possible incendiary device was found at the library, but he appeared to backtrack this evening, saying only that authorities were investigating at the scene.

The fire started just after 3 p.m. in the vicinity of HVAC equipment in a section of the building opened in 2011 that houses offices, a classroom, and some archival material, said library spokeswoman Rachel Flor. The fire was quickly extinguished.

“Everyone is safe here,” Flor said. “There was a fire, and it’s still unclear how it began.”

Flor added: “We did hear something that sounded like an explosion.”

Update: Be careful of graphic images, but this is a Boston Globe photographer’s first-hand look on the scene.

Update: Hmm, from local sources, but not confirmed connected to the bombings. I’ll update as they clarify on developments in Revere.

More from Revere, still floating around on Twitter without confirmation, so take it with a grain of salt until we know it’s connected:

Update: An eerie photo from earlier today, of marathoners stopped within the last mile of the race, via The Globe and Deadspin:

Marathon

And, here’s a new angle on the first explosion, from the perspective of a runner about to finish his race:

Update: The Boston Police and FBI announced the next press conference will be tomorrow morning at 9:30 a.m.

Update: ABC’s Jon Karl finally confirms what the NY Post reported much earlier today about a “person of interest” being guarded in the hospital, who was a Saudi national (the Post may also have referred to him as a “suspect,” which doesn’t seem to be the case). There was a lot of second guessing of the Post going on, and Fox bashing, when Fox shortly thereafter confirmed there was a “person of interest,” but did not designate a nationality. More on that “person of interest,” who is indeed Saudi, apparently.

Update: More from Revere:

A law enforcement source tells Fox 25 that a large police presence at a home in Revere is related to the Boston Marathon bombings.

The source said that a suspicious driver was pulled over by Revere police after driving past the State Police barracks a number of times.

The driver reportedly had a “nervous demeanor.”

The driver then led police, as well as the FBI, to a home in the area of Ocean Avenue and Beach Street.

It was not immediately known what police were searching for at the home. Three people died and more than 100 were injured after bombs went off within 100 yards of each other near the finish line of the Boston Marathon Monday afternoon.

I imagine we’ll find out much more about this tomorrow at 9:30.

Update: The police have reportedly left the scene without talking to reporters.

Update: We’ll end the night on as uplifting a note as possible.

The public Google doc for offering up places to stay in Boston to stranded marathoners and spectators is a testament to the reflexive kindness of our people.

In New York, a lovely tribute to Boston on the side of the Brooklyn Academy of Music:

In Oakland, cheering for Boston:

And, an inspired catch by a man named, fittingly, Ben Revere:

Here’s his glove: