Hundreds of people gathered in southeast London on Friday night at a vigil for Sabina Nessa, a 28-year-old woman who was found dead in a park, the latest case to spark public concern about women's safety.

The primary school teacher disappeared a week ago after leaving her home to go to a bar just five minutes' walk away.

Her body was found by a member of the public the following day hidden in a pile of leaves.

The young woman's death, like that of 33-year-old Sarah Everard in March this year, has galvanised public opinion over the safety of women in public spaces.

Carroll, a 35-year-old teacher who attended the vigil carrying lilies, told AFP that Nessa's death had caused her to fear for her own safety.

"She's a woman and a teacher so I feel kind of close to her," she explained. "I usually walk through that (park) to go to the gym. It could have been any one of us that day, so I'm still shaking. I'm still panicking."

In response to Nessa's death British Prime Minister Boris Johnson wrote on Twitter that his "thoughts are with the family and friends of Sabina Nessa at this deeply distressing time".

"I will be thinking of them tonight as people come together to pay their respects. We will do everything we can to prevent these abhorrent crimes and make our streets safer," he added.

As she paid her respects to Nessa, Emma Thomas, 27, from the nearby London area of Peckham said she had been left "completely devastated and angry" by the killing.

Echoing criticism that has come from some quarters, she said Nessa, a British-Bangladeshi, had received less attention in news bulletins in comparison to the reaction to recent disappearances of white women.

"I think that white women are often covered more in the media, the whole kind of missing white woman syndrome issue," she said.

"Of course they're all tragic events but I think it's really important that we ensure that everyone gets the same kind of attention and outrage," Thomas added.

At a news conference on Friday Assistant Commissioner Louisa Rolfe said police were looking for a man seen near where Nessa went missing on CCTV.

Two men arrested on suspicion of murder in recent days have now been released pending further investigation while detectives remain keen to trace the third captured in on camera.