West Mercia Police says officers are guarding the tragic scene where a member of the public made the grim discovery on Saturday evening.
The alarm was raised at 9.15pm and emergency services went to the riverbank, finding the remains, confirmed to be human.
Police say they had been in the water for some time. They were removed to a mortuary.
A spokesman said on Monday that investigations were continuing and interviews in connection with the discovery could take place over the coming days.