An electrical fire in the Massachusetts Statehouse's basement forced hundreds of lawmakers, employees and visitors to evacuate Tuesday afternoon, and the seat of state government will remain closed Wednesday.
No one was injured in the incident, which first responders said generated significant volumes of carbon monoxide and required power to be shut down.
Firefighters responded to the capitol shortly after 2 p.m. and found "a lot of smoke coming from the vault area" in the basement, Boston Fire Department Commissioner Paul Burke told reporters around 4:45 p.m. They determined that high-voltage wires that feed into a transformer, but not the transformer itself, were ablaze.
Electrical equipment was damaged, and the basement sustained some smoke damage, but there was no other structural damage, Burke said.
Next steps still were not entirely clear when Burke addressed an assembly of cameras at the corner of Myrtle and Hancock streets.
"The power company is going to evaluate. Once the burning is stopped and it's cooled down, they'll evaluate how to circumvent that area, whenever they can do. They could probably fire up two [high-voltage feeds], maybe, and have enough service, but that's up to them," he said.
The Bureau of the State House said around 7:45 p.m. that the building would remain closed Wednesday.
Burke said officials are still investigating what caused the wires to catch fire, though he said the equipment did not appear to be old or outdated.
"It could have been the demand because of the air conditioning, it could have been anything," he said.
First responders spent some time on the two-alarm scene standing by in hazy July weather, waiting for NSTAR to isolate the affected transformer by shutting down power.
State Police reported in the afternoon that fire officials were waiting on utility workers to cut power "before they make entry to extinguish the fire" and said "there are smoke conditions in other parts of the building."
Later in the afternoon, State Police spokesman David Procopio said that "the room where the fire occurred is being vented in order to allow NSTAR to localize and shut off the feed that is believed to have caused the fire."
Burke said it was a "lengthy process" to help NSTAR workers shut off power via manholes. Responders needed to suit up with safety equipment and a "security rope" in case they need to exit quickly, Burke said.
"It was in a tunnel and the the smoke and the quality of the air -- toxins in that burning materials were very dangerous," he said. "For carbon monoxide, an average reading might be 10 or 11 parts per million. This was in the thousands. So it's not sustainable for humans to not be on oxygen, on air that we have the firefighters on, so they had to go down there with their equipment on."
Elected officials, staffers and others departed the building when initially instructed, many leaving behind personal belongings. Fire apparatus arrived at about 2:20 p.m. on the Bowdoin Street side of the building, where building occupants were amassing.
Just before 2:30 p.m., a State Trooper said, to cheers from some on the street, "Folks, the building's probably going to be closed for a few hours, possibly the rest of the day. I recommend the 21st Amendment."
Gov. Maura Healey walked out of the building at 2:23 p.m. carrying a backpack, and appeared headed for her car, which was running under the arch near the corner of Mount Vernon and Hancock streets but ultimately remained in place. Lt. Gov. Kim Driscoll was outside as well and said she was "safe."
Many lawmakers and staffers departed the area while the emergency response was continuing. Auditor Diana DiZoglio, who once worked as chief of staff for the Professional Fire Fighters of Massachusetts, was one of the most visible elected officials who remained at the State House, handing out bottles of water and helping workers who had left belongings inside.
The evacuation was in fact the second of the day. On Tuesday morning, the building briefly emptied out after two people activated an emergency alarm in the capitol, according to building managers.
An alarm sounded just before 11 a.m., disrupting committee hearings and pushing lawmakers, staff and tourists out into the hazy weather. Crowds huddled on the sidewalks until they were allowed back inside after around 15 minutes.
When the second alarm of the day went off, lawmakers, government officials, staffers and members of the public — many of whom seemed to think it would be another brief interruption — mulled about until state troopers began to shepherd them from the area around the State House, saying "This isn't a drill."
"The Boston Fire Department is on scene and has determined that the fire was confined to the basement. Due to ongoing concerns regarding elevated carbon monoxide levels, however, the State House will remain closed for the remainder of the day. Bowdoin, Beacon, Hancock and Dern [sic] streets are also currently closed to the public," Tammy Kraus, superintendent of the State House, said in a statement around 3:45 p.m.
The building closure occurred as Democrats continue to haggle over details of an overdue annual state budget, amidst an effort in the House to push a gun law reform bill to the floor, and as cities and towns wait for Democrats to end their stalemate on a road and bridge funding bill.
Asked what his agenda would entail once he regained access to the building, House Ways and Means Committee Chair Rep. Aaron Michlewitz replied, "Work."
Senate Minority Leader Bruce Tarr said he's optimistic lawmakers will be able to "absorb" the disruption without too much of an impact.
"We may have to quicken the pace on a couple of things, but I don't think it will be incredibly disruptive unless we find out that there's damage that prevents the building from reopening in the next day or so," the Gloucester Republican told reporters. "I don't suspect that will happen. But I'm not the expert."
The House had an informal session planned for Wednesday at 11 a.m., but top Democrats scrapped that following the announcement the building will remain closed and now intend to reconvene in an informal session on Thursday. Speaker Ron Mariano's office continued to advise representatives of a potential formal session Friday.
Tarr said he and some of his employees left personal items like keys and wallets in their offices when they evacuated for the second time.
"Right now, they're on the sidewalk planning about how they can give each other rides home — the ones that did exit with keys are going to carpool with the others," Tarr said Tuesday afternoon.
He added with a smile, "I did put out a message to the news corps: I'm happy to catch a ride in a news vehicle as well if anybody's headed to Gloucester."
This story was reported by Chris Lisinski, Colin A. Young, Michael P. Norton, Sam Drysdale, Alison Kuznitz and Sam Doran.