Police are examining a knife found with what appears to be hair wrapped around the handle near the Whampoa River.
The knife, with a 40cm blade, was found not far from where the mutilated body of 33-year-old beautician Jasvinder Kaur was recovered in December last year.
The body was floating in the river wrapped in rubbish bags.
However, police declined to comment on whether the knife may be related to the murder, citing an ongoing investigation.
Factory worker Qu Yong, 48, discovered the knife on Sunday at about 5 pm, when he went to look at fish in the river.
The Chinese national was standing under a bridge at a section of the river near Block 5, St George's Lane, when he saw a dragon handle on a grass patch.
"I thought the dragon handle looked interesting. Then when I pulled it out, I realised it was a knife," said Mr Qu in Mandarin.
"There were maggots and black hair on it."
The knife's blade was wrapped in paper and yellow tape. It was a bit dirty, but had no blood stains and did not smell bad, he said.
Mr Qu then called a friend, a 57-year-old general worker who wanted to be known only as Mr Seah, to examine the knife.
Mr Seah said the hair was wrapped around the handle of the knife.
"I didn't want to go closer to the knife after he told me that there was hair on it," said the St George's resident.
Mr Seah then lodged a police report on behalf of Mr Qu, who does not speak English.
The duo led officers to the scene, and were taken to the Police Cantonment Complex to have their statements taken.
The body of Ms Kaur - without her head and hands - was found in the Whampoa River between McNair Road and St George's Road.
A forklift driver, Gursharan Singh, 25, was later charged with murdering Ms Kaur.
The police are still looking for her husband, logistics executive Harvinder Singh, 33, who had skipped town before her body was found.
All three are Indian nationals.
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