Russia's main security agency says it is punishing a group of newly graduated officers and their instructors after videos showing them parading through Moscow in expensive SUVs earlier this month appeared on social media.

The Federal Security Service gave few details of the incident but said in a July 14 statement that, during an incident that occurred during graduation events, an unspecified number of graduates behaved "immodestly," violating the agency's code of ethics and professional behavior.

The videos, which were published earlier this month and circulated on Russian social media as well as YouTube, showed what appeared to be FSB graduates driving through Moscow in more than two dozen rented late-model Mercedes SUVs, hanging out windows, and posing for the cameras.

One video appears to show the graduates posing for a group photo with the famous towers of Moscow State University in the background, a favorite place for students of all disciplines to take graduation photos.

WATCH: FSB Graduates Parade In SUVs

Another video bears the imprint of a film company whose website advertises photography and videos for weddings.

In its statement, the agency, known by its Russian abbreviation FSB, said the event had attracted the "heightened attention of society," and had sparked "justified concern from citizens and harsh discussion among the military units of the security agencies."

"Principled personnel decisions have been taken toward the guilty individuals, changing the condition of their service. Severe disciplinary measures against the leadership of the Academy, including the demotion of several leaders [and] their firing, will be taken," the agency said.

The FSB, the main successor agency to the Soviet KGB, also suggested that some of the videos circulating may have been doctored but gave no further details.

The stunt sparked outrage among veterans for the Soviet and Russian security services who said it cast the agency in a poor light, and among citizens angered about apparent traffic violations committed by the graduates.

