These reports are coming in from multiple news outlets, the first of which is NBC News:

NBC News: Law enforcement sources say that at this point in the review of the bombs it is clear that some were incapable of exploding. Whether that was a design flaw or intentional is not yet known. Analysis is ongoing They say to treat any suspicious package as if it were real. — Tom Winter (@Tom_Winter) October 25, 2018

NBC Miami has a story up about this which adds a bit more detail. The story also notes that there have already been suggestions the bombs were intended as a threat, not to actually kill anyone:

Some of the 10 suspected mail bombs addressed to high-profile Democrats and others over the last few days were flawed and not capable of exploding, while others have yet to be fully analyzed, several investigators said Thursday. In some cases, the flaws were substantial. In others, more subtle, they said. The news comes after investigators said the devices appeared poorly made and that it was unclear if they were hoaxes or simply cases of bad construction… The latest development could lend credence to a theory NY Gov. Andrew Cuomo mentioned in a Thursday interview with CNN, where one of the devices was sent. “There’s a theory that the bombs were not intended to explode, but were intended to intimidate,” Cuomo said. “If that is the intent, then this is having the desired intent. And it could actually be fueling the group that’s doing it.”

The Associated Press backs up some of this, saying investigators aren’t sure what the intention was here:

Investigators probing crude pipe bombs sent to prominent critics of President Donald Trump are trying to determine whether the devices were intended to detonate or simply to sow fear, law enforcement officials told The Associated Press Thursday. The officials said the devices were not rigged like a booby-trapped package bomb that would explode upon opening. They had timers and batteries but never went off. Law enforcement officials were still uncertain whether the devices were poorly designed or never intended to cause physical harm. The officials spoke on condition of anonymity because they were not authorized to discuss the ongoing investigation by name.

Authorities may be saying this to the media anonymously, but none of the people at the NYPD press conference today, including the FBI, are saying it to the public. Police Commissioner James P. O’Neill was asked at least four times if the devices could be characterized as hoax bombs and repeatedly said that the NYPD was treating them as “live” devices. “We’re not going to give you a 100% accurate description of what the devices were, but we have to treat them as live devices,” O’Neill said the first time he was asked (video below).

I’m speculating here, but it seems to me that even if some or all of the devices were not intended to detonate, authorities are not going to reveal that for fear people would let their guard down. I suspect we will get a more complete account eventually, but not until the person behind this is caught and no longer a danger. For now, best to just assume these could kill someone.

Meanwhile, a separate NBC story reports that investigators have begun to zero in on Florida as the location from which the packages were sent:

Investigators are looking into whether some of the packages were sent from Florida, two senior law enforcement officials told NBC News. Three officials said that they believe all of the packages were sent through the mail.

The NY Times has a story up reporting the same thing, adding that authorities are focused on southern Florida based on photos taken by the postal service:

Federal authorities investigating a spate of pipe bombs sent this week to several prominent critics of President Trump have turned their attention to southern Florida, believing that a number of the explosive devices were mailed from the area, two people briefed on the matter said Thursday… Investigators are now focusing on Florida because an analysis of information collected by the United States Postal Service indicated that many of the packages were mailed from the state. The Postal Service records images of mail that comes into its system. As part of the investigation, officials have been searching those images in an effort to determine where the packages were sent from as well as to identify and catch any other possible explosive devices by the bomber or bombers.

The focus on this is so intense right now that it’s hard to believe the would-be bomber is going to remain at large for much longer. Here’s hoping this creep is behind bars for the weekend. At that point, we’ll start to get some answers about what motivated this.