KwaZulu-Natal police have intensified their search for the son of a 68-year-old paraplegic woman, who was found dead at a Chatsworth nature reserve in Durban.

The police's Search and Rescue Unit found the body of Thanalatchmee Durugan floating in the Silverglen Nature Reserve at about 04:00 on Monday, police spokesperson Lieutenant Colonel Thulani Zwane said on Tuesday.

Durugan and her 46-year-old son Sagren Pillay had been reported missing on November 29, Zwane told News24.

Pillay's car was also discovered at the same nature reserve, Zwane confirmed.

"Police have intensified their investigations in search of the 46-year-old son," Zwane said.

He said Chatsworth police were investigating a case of murder because Durugan was a paraplegic and it was "suspicious" that she ended up in the dam.

"Police are still waiting for a post-mortem report to determine her cause of death," said Zwane.

Zwane said he could not "speculate" whether Pillay was a suspect in his mother's murder because police were not sure whether he was alive or dead.

Police urged anyone who could assist to contact Warrant Officer Cleo Loganathan on 079 837 4182.