First responders from multiple agencies were called to a stretch of US-1 on the north side of the Conowingo Dam after one person reportedly went into the river.
Harford County Fire and EMS personnel, crews from the Darlington Volunteer Fire Company, Water Witch Fire Company, and the Cecil County Department of Emergency Services all responded to the scene.
A Maryland State Police helicopter has also been requested to the scene.
During the investigation, the southbound lanes on US-1 and rail traffic were both shut down.
More details are expected to be released.
This is a developing story. Check Daily Voice for updates.
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