While digging the foundation of an apartment building in the Belarusian city of Brest near the Polish border, construction workers recently discovered human remains believed to come from hundreds of Jews killed by the Nazis during the occupation of Eastern Europe, reports Reuters.

According to the news agency, excavations of the mass grave have been taken over by the Belarus military, and so far soldiers have exhumed 730 bodies, though officials expect to find more in the area. “It’s possible they go further under the road,” said Dmitry Kaminsky, the soldier leading the exhumation unit. “We have to cut open the tarmac road. Then we’ll know.”

Some of the skulls recovered bear bullet holes, suggesting that the people in the grave were executed. During World War II, Brest was part of Nazi-occupied Poland and the site of the grave was part of the Brest Ghetto, a segregated section of the city where Jews and other minorities were forced to live.

The Jewish Telegraphic Agency reports that Brest's Mayor Alexander Rogachuk is currently in talks with local and international Jewish groups about moving the remains to local Jewish cemeteries.

The Brest Ghetto was established after the Germans overtook Poland, and roughly tens of thousands of the city’s Jewish citizens were confined to the area. On October 15, 1942, the Nazis loaded 20,000 Jews onto railcars and transported them to Bronnaya Gora, about halfway between Brest and Minsk by rail, where pits had been prepared. The Jews of Brest were then shot and dumped into the pits along with 30,000 Jews from other cities and regions. In 1944, when the Soviets liberated Brest, only nine Jewish citizens were found to have survived the war.

Belarus has come under fire in recent years for its handling of Jewish and Holocaust heritage sites within its borders. JTA reports that the government has demolished three synagogues—two in Minsk and one in Luban—as well as three Jewish cemeteries.

Kate Samuelson from Vice reports that callousness toward victims of the Holocaust in Brest is decades old. After the war, the Soviets sought to scrub the last vestiges of Jewish culture from the city, dismantling one of the largest Jewish cemeteries in the region to make way for a sports stadium. Locals recycled the headstones, using them in the foundations of houses, as paving stones and in gardens. As of 2014, 1,500 headstones had been found around the city, including 450 dug up during the construction of a supermarket. Many are being stored in the hopes that they could one day become part of a memorial.