The decomposed body of a baby girl was found in a packet on a river bank in Pietermaritzburg on Thursday morning, KwaZulu-Natal police said.

She was believed to be between six and eight-weeks-old and had an open wound to the head, said Colonel Jay Naicker.

She was found by a person passing by.

"At this stage, it is believed that the baby may have been murdered elsewhere and dumped on the river bank," said Naicker.

He said that due to the state of decomposition, she was thought to have been murdered about two weeks ago.