A woman's body has reportedly been found chained by the neck and tied underwater by two concrete dumbbells at a popular fishing spot in Thailand.

The corpse was discovered floating near the Ban Tha Yai pier in Phang Nga on August 8 - sparking grisly murder investigation.

Police Lieutenant Pheerawit Chaichanyut of Khok Kloi Police Station said officers responded with rescue workers after receiving a call from shocked locals.

The victim, whose identity, address, and nationality are still unknown, was wearing grey shorts and a brown round-neck T-shirt, The Thaiger reports.

Police estimate she had been dead for around two days before being found in the murky waters.