D.C. Fire Chief Kenneth Ellerbe said he was personally acquainted with a 77-year-old longtime city employee who died of a heart attack the same day he was denied care by officials at a Northeast Washington fire station.

In an interview with Fox 5 News in Washington D.C., Ellerbe said his department continues to investigate the death of Medric Cecil Mills Jr., who collapsed Jan. 25 on Rhode Island Avenue NW. When people sought help for Mills from the station, they were told by fire officials there that the station’s employees could not help unless they called 911. An ambulance that was dispatched to the scene went to the wrong address. One was eventually flagged down by a police officer. Mills was taken to Washington Hospital Center, where he died.

In the televised interview, Ellerbe, who has faced repeated questions about fire department mishaps and his ability to lead the department, said he takes full responsibility, though not blame, for what happens under his command.

He said the department continues to investigate the Mills incident. According to news reports, the fire department lieutenant who was at the station on the day Mills collapsed is attempting to retire. Two firefighters are on administrative leave and several employees of the station have been questioned, officials said.

Ellerbe said “progress” has been made in the department and indicated that it would be easier to make changes if he had more control to hold people under his command accountable.

Mayor Vincent C. Gray, who also knew Mills, called the incident “an outrage.” Mills was an employee of the city’s parks department when he died.

The Mills case has been compared to a New Year’s Day 2013 incident where a 71-year-old man died of a heart attack after waiting more than 30 minutes for an ambulance. That day, 30 percent of the firefighters on duty called out sick in what some said was a protest against Ellerbe. In March 2013, a D.C. police officer who had been struck by a car was not assisted by an ambulance for 15 minutes because three ambulances that could have responded were not in service.