D.C. Fire Chief Kenneth B. Ellerbe is seen under scrutiny by the D.C. Council at the Wilson Building in Washington on March 28. (Marvin Joseph/The Washington Post)

The D.C. fire department is investigating an alleged confrontation involving Chief Kenneth B. Ellerbe and a firefighter over a picture of a burning ambulance that was taken before the flames were out and that was quickly posted to the Internet.

Ellerbe said he requested the internal affairs inquiry after hearing allegations that he had forcefully grabbed a smartphone from a firefighter’s hands at the scene, which he denied. In an interview Tuesday, Ellerbe said he asked for the phone, looked it over and returned it. He called the allegation “another attempt to distract” his efforts to change the department.

The firefighter has not filed a complaint with the department, the police or an outside agency. The president of firefighters union Local 36 declined to name him and said he is on sick leave because of stress involving his interaction with Ellerbe.

The alleged confrontation was first reported by Washingtonian.

The chief and the union head said they do not know who took the photo during the Aug. 13 emergency call in Southeast Washington. The alleged confrontation over the picture is the latest chapter in what has become a bitter feud between the firefighters union and department leaders over equipment failures, poor response times, vacancies and stalled labor negotiations.

An ambulance caught fire on a call earlier this month on Benning Road in Southeast Washington. The cause of the fire is under investigation. (Courtesy of D.C. firefighters Local union #36)

The photo showing flames leaping from the engine of the ambulance provided an unflattering image of the department as the upkeep and viability of its fleet were being questioned. It was posted on the union’s Twitter page 23 minutes after the first fire engine arrived and was republished repeatedly by the news media, including The Washington Post.

To the union, that fire and another in an ambulance the same day served as opportune metaphors for what it calls an ailing department. To city leaders, the occurrence of two ambulance fires hours apart was suspicious, prompting a deputy mayor to order D.C. police to investigate to make sure “nothing untoward is occurring.”

Speaking on NewsTalk with Bruce DePuyt on NewsChannel 8 on Tuesday, D.C. Police Chief Cathy L. Lanier said the investigation is continuing. She called the fires “a little suspicious.”

The union says its members are not sabotaging vehicles to prove a larger point. The Post reported Sunday that fire investigators determined that the blaze in the photograph was accidental, possibly caused from rubber being too close to the air conditioner. That fire was the most severe of the two, causing $25,000 in damage to Medic 27, a 2006 Ford in the department’s reserve fleet with what one internal report described as a long history of maintenance problems.

The crew was in an apartment helping a patient in the 4700 block of Benning Road SE when the fire was reported at 9:51 a.m. Engine 27, from Deanwood, where the crew is known as the “Deanwood Demons,” arrived at 9:56 a.m. The picture showing flames was first posted on the union’s Twitter page at 10:19 a.m. Engine 27 left the scene at 11:55 a.m.

Edward C. Smith, president of Local 36, said the firefighter told him that Ellerbe “seemed very irate and wanted to know who had shot what on the phone.” Smith said the firefighter told him that the chief grabbed the phone from his hand but then gave it back. “The department should have a zero tolerance for workplace harassment or violence,” Smith said.

Ellerbe said he responded because he considered an ambulance fire significant and because he had seen the photo on Twitter. He said he approached firefighters and asked whether anyone had a phone. He said one answered yes. “I said, ‘Can it see it?’ ” the chief said. “He voluntarily handed it over. I looked at it. I wanted to see if it had camera capability.” He said the screen was dark, “and I handed the phone right back to him.”

He said he’s not sure that a firefighter took the photo, although he noted few civilians would know to send the picture to the union. He also said he didn’t think the firefighter he first approached took the photo.

Firefighters often take pictures of fires and traffic accidents, and many find their way to social media, which include the union’s Facebook and Twitter sites but also pages run by fire buffs, such as Statter911.com, which posted a picture of Ellerbe at the fire scene talking on his cellphone, the charred ambulance in the background. Deanwood’s Engine 27 has an Internet page, showing firefighters putting out fires and rescuing people from overturned cars as well as pictures of one firefighter’s newborn child.

The D.C. Fire and Emergency Medical Services Department does not have a policy about social media. But Ellerbe said on-duty firefighters should not be snapping pictures of fires and distributing them publicly.

“I’m hoping they were too busy fighting the fire to take a picture,” he said.

He said he wanted to make sure the damaged ambulance was quickly towed away. “I thought my presence would initiate a faster response in removing the vehicle from public view,” he said.

Jennifer Jenkins contributed to this report.