The remains were recovered from the Charles River near the Boston University Bridge and Sailing Pavilion, just after noon.
Officials with the medical examiner's officer were on scene to assist in the investigation.
There is no word on who the remains belong to or how they got in the river. A source tells FOX 25 that what police recovered was a human leg.
The investigation is ongoing, but State Police assured the public that "based on the investigation to date," the partial remains discovered do not pose an ongoing threat to public safety.
FOX 25's Bob Ward contacted the Suffolk County District Attorney's office for comment and was were referred to the Essex County District Attorney's office.
State police there are investigating a brutal homicide case FOX 25 has also been following.
Back in November, burned body parts were discovered on the grounds of Bridgewater Psychiatric Hospital, and in Hyde Park.
The Plymouth County District Attorney identified the remains as those of Dennis Ray Jackson of Haverhill.
A severed head was found in the Charles River in January, and the Essex County DA said at the time that discovery is likely related to the burned body parts found in November.
Reggie Cummings, 26, has emerged as a person of interest in the case. Shortly after the Jackson murder, Cummings fled to Mexico, but he was picked up on unrelated warrants in December.
In April, Cummings was charged with illegal disposal of a corpse and accessory after the fact in this case. He is being held without bail.
Jackson and Cummings, both shared a condo in Salisbury.
This story is developing. Stay with FOX 25 and MyFoxBoston.com for the latest.
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