Two top officials in the D.C. government’s property security department were fired Wednesday.

Chief Louis Cannon and deputy Benjamin Pietra were fired from their posts atop the Protective Services Police Department, which handles building security and law enforcement on D.C. government property. Pedro Ribeiro, a spokesman for Mayor Vincent C. Gray (D) confirmed the dismissals.

Ribeiro declined to comment on the reasons for the firings but said both were considered “at-will” employees.

Two sources familiar with the decision to fire Cannon and Pietra said the dismissals were related to an October incident in which Occupy protesters marched on the John A. Wilson Building and replaced a D.C. flag there with an Occupy banner.

An investigation found that top officials filed a report containing false information about the incident without interviewing department personnel on the scene, one source said. The sources also said Cannon is under investigation over allegations that he donated unused department radios without following city procedures.

Cannon has attracted scrutiny for receiving pension benefits from his two decades on the D.C. police force while serving as Protective Services chief. The Washington City Paper reported on the situation in December, shortly after the city personnel department said that Cannon and other city employees must have their salaries offset by the amount of their pension payments.

Cannon and five other former D.C. police officers affected by the decision to end the pension payments sued the city in federal court last month.

Matthew LeFande, an attorney for Cannon in his lawsuit against the city, said he was “very concerned” about the firing, given its proximity to the litigation.

“I’m going to be very, very skeptical of anything that’s offered as a pretext given the circumstances here,” he said. “It smacks of retaliation.” Pietra could not be reached for comment.

Cannon earned $110,000 a year as chief, according to a list of city employee salaries published in September; Pietra earned about $121,000.

Assistant Chief Rodney Parks of the D.C. police is serving as interim head of Protective Services, a department spokeswoman said.