Opponents of Ward 4 D.C. Council candidate Muriel Bowser thought they had her nailed for some type of high-profile ethical gaffe. It looked as though Bowser patron Mayor Adrian Fenty had finally crossed the line in his support for his candidate.

This weekend, several residents spotted what appeared to be a D.C. fire truck sporting a green and white Bowser banner. Some citizens even reported that the fire engine was running with sirens on full blast. Of course, Bowser’s opponents were quick to hit cell phones and listservs to charge the mayor with ordering his fire department to get behind Bowser.

Not quite.

It was the firefighters’ union out there for Bowser. The Muriel Bowser for Ward 4 truck was a private vehicle regularly used by Local 36 of the International Association of Fire Fighters Association during the political season. The group has endorsed Bowser and admits blasting the sirens as they slowly moved around the ward’s back streets.

But union president Dan Dugan denies the siren was ever used on a major street. “We only turned [the siren] on briefly when we were on a block,” says Dugan. “Then we shouted support for Muriel and handed out some T-shirts.”

Dugan was shocked to see his activities lighting up the political gossip lines. “The truck is an antique that has been out of service since the 1970s,” says Dugan. “We’ve done this for like the last five or six elections. We’ve never gotten stuff like this.”

Incidentally, the union didn’t support Fenty during the last election.

Bowser appreciates the support of the union, but “we were not happy about the confusion,” caused by the use of the sirens, she says.