Tulsa officials have begun excavation on a possible mass grave site where the victims of the Tulsa Race Massacre could be buried. Almost a century ago, hundreds of Black people were attacked and killed by white rioters, who looted and burned down their community. According to CNN, the search for the potentially buried victims — which was set to begin in March but was delayed due to COVID-19 — resumed on Monday (July 13).

“This is a historic day for Tulsa and for our country,” Tulsa Mayor G.T. Bynum wrote on Facebook. “It should not have taken 99 years for us to be doing this investigation. But this generation of Tulsans is committed to doing what’s right by our neighbors and following the truth wherever it leads us.”

The excavation plan began after a geophysical scan of the Oaklawn Cemetery indicated there were underground anomalies consistent with a mass unmarked grave site, including seemingly human-dug areas.

“Our work continues to find the graves of our fellow Tulsans who went missing during the 1921 Tulsa Race Massacre,” Bynum’s post continued. “… Because the scan is consistent with a mass grave, a team of some of the foremost researchers in the nation have assembled in Tulsa to assess both the presence and the condition of any human remains at the site in question.”

In 1921, white rioters burned down 35 blocks of Tulsa’s Greenwood section — an area of thriving Black-owned businesses and residences that has come to be known as Black Wall Street. The massacre continued for two days until martial law was declared. Black survivors weren’t allowed to claim their deceased relatives and their bodies were buried by strangers. The tragedy’s official death toll is 35, but many historians believe up to 300 Black lives were lost.

“The ultimate goal here is to be able to connect the victims of this event with their family,” Bynum continued. “That is a tremendous challenge. That is not something we’d expect to have wrapped up at the end of the year. That’s something that will take years to do.”

Speaking with the Washington Post, J. Kavin Ross — whose great-grandfather owned a business that was destroyed during the massacre — said he’s eager to find out the truth.

“I’ve waited for this day for over two decades to find out the truth of Tulsa’s public secrets,” Ross said. “A lot of people knew about it but wouldn’t tell about it.”

The excavation is expected to take three to six days.