Police are investigating after a passer-by found a pile of bones by the Thames.
Recruitment co-ordinator Clare Taylor made the "gruesome" discovery near Greenwich Pier while out with friends on Sunday.
The 26-year-old, from Kilburn, was walking along a path overlooking the Thames outside the Old Royal Naval College when she noticed what she said looked like a human thigh bone.
"We walked down the steps and there were thousands and thousands of bones," she told the Standard.
"And they definitely seemed real because they were hollow inside. We picked them up and put them on the pavement.
"The worst moment was when we picked up the set of teeth, but they don't look human."
Among the remains were also what appears to be part of an animal's jaw and several smaller bones.
But it was the discovery of the larger item - which Ms Taylor said seemed like a thigh bone, or femur - that prompted the friends to call the police.
"It was a bit surreal," Ms Taylor added.
"A couple of the group were like 'it's probably nothing, let's go'.
"But I thought what if it was a human bone linked to a murder.
"London has lots of murders that are unsolved. It was gruesome."
A spokeswoman for the Metropolitan Police said officers were called at 2.50pm by a member of the public claiming to have found bones near the Old Royal Naval College.
Officers have seized the items and are investigating whether the remains are human or animal, she added.
