TULSA (AP) — Tulsa will resume test excavations of potential unmarked graves from the 1921 Tulsa Race Massacre after the effort was halted in March because of the coronavirus outbreak, city officials announced.

The pandemic’s travel restrictions have made it difficult for the archaeology team to reach Tulsa’s Oaklawn Cemetery for an examination, which was initially set to begin April 1. The state archaeological survey at the University of Oklahoma includes scientists from out of state.

The test excavation is expected to begin next Monday, Tulsa World reported Tuesday.

Tulsa Mayor G.T. Bynum said his city is committed to the project that’s aimed at identifying potential unmarked graves of the dozens of Black people who were killed by white mobs in Tulsa’s Greenwood district in 1921.