The Russian government has been consistently under-reporting their casualty figures from the Syrian Civil War, a Reuters investigation has found.

After a combined effort from Reuters and the Conflict Intelligence Team investigative group, researchers found that Russian casualties were actually three times the amount of what was being officially reported by the Russian government, and that many of the deaths were from private military contractors.

As a whole, Russia has been largely quiet about combat casualties this year. The independent investigation, which verified each combat casualty by speaking to family members and friends of each deceased soldier, confirmed a rapid uptick in casualties coinciding with the second offensive to retake the city of Palmyra.

The Syrian Army, with the assistance of Russian regulars and paramilitaries, retook the ancient city earlier this month.

Since the start of 2017, the Russian government has only officially acknowledged the deaths of five soldiers. Investigators found that 18 Russian citizens, through a combination of regular army and private contractors, have been killed since January 29th.

Official acknowledgment is spotty for a number of reasons, one of which is the delicate political situation involved in deploying ground forces to the fight. At the outset of the war, Russia was officially providing only air support, humanitarian aid, and fire support in the form of forward controllers directing air strikes. Losing Russian Marines, Infantry, and Special Operations forces would be indicative of a much more significant Russian contribution to the fight in Syria.

Another reason is that the deaths are unpopular for domestic politics. So much so, that Putin has moved to actively suppress reports in the media of combat deaths from the campaigns in eastern Ukraine and Syria, going so far as to make disclosing details of casualties from combat a crime in 2015. As Putin approaches another presidential election which looks to give him a fourth term, he is likely attempting to de-emphasize casualties in an operation he officially declared over last year.

The fact that most of the dead are private contractors, which are not officially acknowledged to even be operating within Syria, further illustrates the length to which Russia is acting to conceal the toll of combat operations on their military.