NPR reported the crew discovered a pit measuring roughly 30 feet by 25 feet. They said it was large enough to fit up to 100 bodies.
At the time, Tulsa Mayor G.T. Bynum speculated whether the “underground anomaly” was in actuality a mass grave.
"It should not have taken 99 years for us to be doing this investigation," Bynum told reporters Monday, according to NBC News. "But this generations of Tulsans is committed to doing what's right by our neighbors and following the truth wherever it leads us."
Bynum has also been providing updates about the excavation on his official Facebook page.
The tragic events in Tulsa more than 99 years ago recently got renewed attention after President Donald Trump scheduled a campaign rally in Tulsa for Juneteenth, which Black Americans annually celebrate on June 19 as the day when the last U.S. slaves were freed.
Trump rescheduled the event for the following day after backlash from Black leaders who found the president's timing troublesome.