A road of bones has been discovered in Siberia. Human remains buried in the sand could date from the civil war lasting from 1917 to 1922. Officials have opened an inquiry as to how they got there, buried in sand, spread over a local road. So far, the bones discovered have been from at least three different people, a Kirensk city official speculated, saying the bones could date back to the civil war in Russia.

Photographs first appeared on social media and locals argued over whether the bones came from a cemetery nearby or a ravine rumored to have been used as a mass grave.

Nikolay Trufanov, local legislator for the ruling party, said, “Sand with skulls and bones has been spread on the roads in Kirensk,” in a Facebook post, adding that using previously accessed knowledge they determined, “utility workers took sand from space near a cemetery. I can’t even describe how monstrous it is.” He hopes those responsible are punished.

Human remains are sometimes found during construction and road work in Russia, mainly near WWII battle sites in the West. What remains of at least ten people suspected to be Red Army soldiers were found in 2014 during highway construction in the Kursk region. In 2018, workers in the neighboring country of Latvia found remains that led to discovering almost 150 bodies.

What was found in Siberia was likened to the Kolyma highway, a 1,250-mile road from near Yakutsk to Magadan that was built under Stalin’s reign using gulag labor. Gulag was a system of labor camps in the Soviet Union from 1930 to 1955, imprisoning millions. The new highway is nicknamed the “road of bones” for the approximately 250,000 who gave their lives in the creating of this highway.

The bones discovered in Kirensk were collected and road work suspended indefinitely, while investigators are looking into a local contractor suspected of collecting sand from too close to a burial plot and failing to inspect and clean it before spreading it on the road.