D.C. Mayor Muriel E. Bowser said Thursday that three days after a Metro passenger died and others were injured, the city still has not been told what time a train crowded with scores of passengers became disabled and began filling with smoke in a tunnel in downtown Washington.

She also said she is concerned about a 13-minute delay between when firefighters first arrived on the scene and power was cut to the electrified third rail so that rescue operations could begin in the tunnel near the L’Enfant Plaza Metro station.

“Like all of you, there are still questions that remain that I want answers to,” Bowser (D) said, “including . . . that we did not know the time that the train actually became disabled on the tracks or the time that the first smoke appeared.”

Two days earlier, Bowser had declined to discuss response times or problems that may have delayed the emergency response, saying it would be “irresponsible” for her to do so as the National Transportation Safety Board began its investigation into the tragedy that killed a 61-year-old Alexandria woman and sent more than 80 other people to area hospitals.

But amid growing outrage from Metro riders and others over a perceived lack of transparency about why train passengers were stranded for at least 35 minutes, Bowser changed course Thursday.

A Metro passenger filmed the scene inside the stranded Metro car, in which people can be seen helping and comforting each other. A Yellow Line train abruptly stopped and filled with smoke in a tunnel in downtown Washington on Monday. (Saleh Damiger/YouTube)

She vowed to release all information the city had “as fast as we can.”

On Thursday morning, City Administrator Rashad Young published an initial timeline of the emergency response, first reported Wednesday by The Washington Post. Bowser said that timeline would be augmented by Saturday with the release of a summary of more than 100 pages of radio communications from the incident and interviews now being conducted with first responders who arrived on the scene.

Preliminary findings of a second, broader citywide investigation, being led by the District’s homeland security agency, would follow by the end of next week, Bowser said.

Asked if reports that firefighters’ radios would not work in the Metro tunnel would be part of that investigation, Bowers said that would be a “significant component.”

“There has been a lot of discussion about if the firefighters could hear amongst themselves, and upstairs. . . . I expect we will have some answers to those questions,” she said.

During the mayor’s news conference at the John A. Wilson Building on Pennsylvania Avenue NW, Bowser never singled out the Washington Metropolitan Area Transit Authority or any other agency for withholding information, but she began to draw a line between the city’s response and that of other agencies.

She said WMATA still has not given the city information about when it first knew that the train was in trouble. Asked if she was concerned about a 13-minute gap — between 3:31 p.m, when firefighters arrived at the scene, and 3:44 p.m., when they were able to safely enter the tunnel — Bowser said yes. However, she said early indications were that radio communications released Saturday would begin to shed light on that time period.

“We share Mayor Bowser’s desire for a public airing of the facts and, to that end, we are cooperating fully with the NTSB investigation, including providing interviews, documents, recordings and access to investigators,” spokesman Dan Stessel said. “Metro is a party to the NTSB investigation, and the federal regulations are very clear: All information regarding the investigation must flow through NTSB.”

Bowser said the job of the fire department and the city’s 911 center to sort through radio communications has not been easy. There are six hours of radio transmissions, and communications were conducted simultaneously on five channels, Bowser said. A computer printout of the call logs is more than 100 pages, she said.

Bowser said that as her administration makes sense of the log and roots out concerns, such as those raised by firefighters about radios, the public would begin to get information at the same time it is shared with WMATA. Bowser suggested she expected the same in return from the Metro board, which she served on for much of the past four years.

“We will be releasing information as it becomes available,” Bowser said. “We do know this, that we had our brave men and women of the D.C. Fire and Emergency Medical Service evacuate 200 people from the system in very challenging conditions. We also know that 84 people were transported to area hospitals.”

Passenger Carol I. Glover, who co-workers said suffered from asthma, died after she was transported from the train at 4:25 p.m. That was roughly an hour after Metro placed an emergency call to D.C.’s 911 center warning that people in L’Enfant station could “barely breathe” from heavy smoke. Glover died of acute respiratory failure, due to smoke exposure, the District’s Office of the Chief Medical Examiner said Thursday evening. The office said the manner of death was accidental.

According to the outline of emergency calls released Thursday by Bowser’s administration, there was no indication that WMATA relayed a concern about passengers also being stranded in a train until later — possibly as much as 20 minutes later. That would have been well after firefighters had arrived on the scene, and passengers on the train had begun calling 911.

Bowser said there should be an urgency to the sharing and dissemination of information “to ensure that our response was as it should be, to find out if there are any areas where it wasn’t, and make sure we fix them.”

Asked if Metro riders should feel safe riding the system, Bowser offered a less positive answer than two days before.

On Tuesday, Bowser said that from her vantage point as a former Metro board member, she believed the culture of safety at Metro had “dramatically improved” since the 2009 Red Line disaster, which killed eight riders and a train operator. “That’s why it’s shocking and so disappointing that we’ve had this failure,” she said.

On Thursday, Bowser answered differently, casting the incident, and the questions it raised about the District’s ability to respond to a disaster, as more troubling — possibly an indicator of more work to be done than as an aberration of an improved system .

“I think that there are a lot of questions that remain and . . . we have to make sure that the response, and our fire department responded, in every fast and safe way possible,” she said.

Bowser continued: “We know that our Metro system carries almost 1 million people a day and it has been operating since Monday carrying people,” she said. “Our focus now is to make sure that all of the government entities responsible for Metro are doing everything possible to make it safer as fast as possible.”

The last of 18 patients were released Thursday from Washington Hospital Center.

Peter Hermann, Lori Aratani, Paul Duggan and Mary Pat Flaherty contributed to this report.