The affected schools were Morningside, E. Rivers, and Springdale Park elementary schools, according to the district. Atlanta Public Schools Police, working with other public safety agencies, searched each building before giving the all-clear.

"All students and staff remain safe while Atlanta Public Schools Police, in coordination with our public safety partners, investigate the threats and conduct thorough searches of each school building," the district said in a statement.

Virginia-Highland Elementary School was not evacuated but was placed on an exterior lockdown as a precaution, and families there were notified.

Outside Morningside Elementary, parents waited as the campus was secured. Gina Gondron, a parent, described the morning as frightening. "It's terrifying, I don't understand why people would do this," she said.

The threats arrived by telephone at each of the three schools, according to information gathered at the scene. It was not immediately clear who placed the calls or whether the threats were connected.

Bomb threats against schools are treated as criminal matters, and districts typically conduct full sweeps of buildings before returning students to classrooms. The district did not say whether any devices were found, and no injuries were reported.

Monday's evacuations disrupted the school day for three intown Atlanta communities and underscored the strain that threat incidents place on students, staff and families, even when no danger is confirmed. The district said its investigation is ongoing.