The victim apparently went to the camps to get back the money some refugees took as loan back home in Myanmar.
Police have identified the victim as Rabindra Paul, 42, one of the hundreds of Hindus who crossed the border into Bangladesh after fleeing violence in Myanmar along with hundreds of thousands of Rohingya Muslims in a month.
The Hindu refugees have taken shelter in an area near the camp for newly arrived Rohingyas in Kutupalong.
Ukhia Police Station OC Md Abul Khayer told bdnews24.com that Rabindra's body was found in Balukhali canal at Palongkhali.
Police recovered the body in the morning but could not identify him, OC Khayer said.
There was no sign of injury on Rabindra's body, but his face was disfigured, he added.
Later, his relatives identified him at state-run Cox's Bazar General Hospital.
Ukhia Puja Udjapon Parishad President Swapan Sharma Rony said Rabindra, his brother Nirendra Paul and nine other Hindu refugees went to the Kutupalong refugee camp a week ago to retrieve money from some Rohingyas they borrowed in Myanmar.
A group of Rohingyas in the camp held them hostage. Nine of them managed to flee but the two brothers could not, the leader of the local Hindu community said.
Nirendra was yet to be found, he added.
The council's General Secretary Babul Sharma alleged the Rohingya refugees killed Rabindra.
OC Khayer said police were investigating the allegation.
"We will take legal action against those responsible for it," he added.