A fisherman found partial human remains near the Peninsula Expressway Bridge in Dundalk on Wednesday morning, Baltimore County police said.
After discovering the remains, the fisherman called 911, police said.
Police said homicide detectives descended upon the bridge in Dundalk shortly thereafter.
Dive teams soon followed, police said, spending much of the day searching the waterway for more remains.
Detectives continue to investigate, according to police.
Police encourage anyone with information about the human remains, the identity of the person or the circumstances around their death to call investigators at 410-307-2020.
This story will be updated.