WASHINGTON — Three times people banged on the door of the Northeast Washington firehouse seeking help for a man who had collapsed. Each time, the rescuers inside turned them away.

In a nearby parking lot, Marie Mills cradled her 77-year-old father in her arms. “Help is on the way,” she told him. “There are firefighters right across the street.”

But the firefighters didn’t come. When she spotted one standing in an open bay door, she ran to the curb. “Can you just come and help my dad?” she screamed. “What are you going to do, let my dad die in the street?”

Mills said she was told by people who tried to help that the firefighters said they couldn’t respond unless someone called 911. It took 15 to 20 minutes for help to show up on Saturday, she said, and then arrived only because a District of Columbia police officer flagged down an ambulance that happened to pass by. Her father, Medric Cecil Mills Jr., died of an apparent heart attack at MedStar Washington Hospital Center that afternoon. He had worked for the District of Columbia parks department for over four decades and liked his job so much that he hadn’t retired.

“There are no words to describe how this city has failed,” Mills said on Wednesday.

District of Columbia authorities are investigating Mills’ death and have ordered 15 firefighters on duty that day to headquarters for questioning. One was told to drive in from his home in Pennsylvania.

Although details of what transpired in the station are under review, the basic outline of what Mills has said is not in dispute. The incident was first reported by a Washington-area TV station, WTTG.

“I’m quite disturbed and disappointed by what appears to be an inappropriate response,” said Paul Quander Jr., the deputy mayor for public safety. “Mr. Mills was someone that worked for the District for a number of years, and the pain and the anguish that the family has gone through is unacceptable. There will be no rush to judgment, but we will be thorough, we will be precise and then we will act.”

Quander said nothing should stop a firefighter from helping someone in distress. “They don’t wait to be called,” he said. “We should have responded to this incident.”

D.C. Mayor Vincent Gray said that “appropriate action should be taken” against anyone found to have acted contrary to the job’s responsibilities. “Frankly, on its face, it’s really hard to accept what happened here,” he said.

Not the first time

The case comes amid reforms being implemented after the 2006 death of retired New York Times reporter and editor David Rosenbaum. Rosenbaum died after District of Columbia emergency personnel mistook the effects of injuries from a vicious mugging for public intoxication and labeled the incident low-priority.

The District of Columbia’s fire department and its chief, Kenneth Ellerbe, more recently have faced scrutiny after problems that raised questions about patient care. On New Year’s Day 2013, a 71-year-old man died of a heart attack after waiting more than 30 minutes for an ambulance on a day when one-third of the firefighters on duty had called in sick.

In March, a District of Columbia police officer who was struck by a car waited 15 minutes for an ambulance; authorities later found that three ambulances were improperly out of service.

Ellerbe, Gray and Edward Smith, the president of the District of Columbia firefighters union local, called Mills’ daughter to express their concerns.

“On behalf of all D.C. firefighters, I offer Mr. Mills’ family a sincere apology,” Smith said.

D.C. Council member Tommy Wells said that the longtime District of Columbia worker “deserved better” and promised that the public safety committee he chairs would hold hearings on the matter.

Tim Wilson, a fire department spokesman, said everyone working assigned to Engine 26 and Truck 15 that Saturday afternoon is being questioned. The firefighter who is accused of refusing to help was hired in the past year and has not yet passed probation, city officials said.

When someone seeks help at a firehouse, procedure calls for the officer in charge to be notified and to decide what action to take. Wilson and Edwards said the probationary firefighter may have told superiors, and the investigation is focusing on who knew about the pleas for help and on why no one acted.

Kenny Lyons, who represents paramedics in a separate labor union, said that emergency workers are barred from “self-dispatching” — such as responding to calls on their own — but that nothing stops them from rendering help or investigating a request from a citizen.

“If you see an incident occurring in front of you, you have a duty to go over an investigate,” Lyons said. “What bothers me in this case is it appears they didn’t even go and check.”

Daughter: Firefighter stood with arms folded

Marie Mills said that she and her father were at a Washington shopping center on Rhode Island Avenue NE and had just dropped off a broken computer at a repair shop. They were walking out, chatting and joking about her returning to college, and he told her, “You get them, college girl.” Just then he stopped talking and tumbled to the pavement.

She couldn’t find her cellphone so she ran back into the computer store and shouted for people to call 911. She and others ran outside and noticed the fire station across the street in the 1300 block of Rhode Island Avenue. She said several bystanders ran over to get help.

“Several people told me the guy behind the door wouldn’t open the door,” Mills said. “He told them, ‘There’s nothing I can do if my lieutenant doesn’t tell me to go.’ ” She said the same firefighter was seen later in the open bay door, leaning against a truck, with his arms folded. “People went over at least three times,” said Mills, who didn’t want to leave her father’s side.

Authorities said it appears that a firetruck dispatched from another station as a result of 911 calls made by the people in the store went to a corresponding address in Northwest Washington, an issue that is also under review. Wilson said the initial report indicates that a police officer flagged down a passing ambulance.

Engine 26 — from the station across the street — was out on a call but eventually responded as well, he said. Truck 15 was in its station when Mills collapsed.

Mills described her father as someone who loved the District of Columbia and the Washington Redskins and often stopped to give a ride to a stranger he saw standing in the cold at a bus stop. He once bought socks for a man. “My dad never met a stranger,” she said. “He met a friend.”

Details of services were still being made Wednesday, but Marie Mills said the funeral would probably be Feb. 8 in Washington’s Mt. Pleasant neighborhood at Canaan Baptist Church, founded by her late grandfather in 1947. Survivors include her brother, Medric Mills III, who is a pastor in the District of Columbia, and Medric Mills’ wife, Sandra, who is 75.

Washington Post staff writer Mike DeBonis contributed to this report.