The Duchess of Cambridge said she was “saddened by the loss of another innocent young woman on our streets” as murder probe police continued the hunt for Sabina Nessa’s killer.

The duchess commented as an estimated 500 peopled gathered at a candle-lit vigil for the 28-year-old primary school teacher, who was attacked and killed a week ago on her way to meet a friend.

Detectives have released footage of a man they wish to speak to over the death, in Kidbrooke, south-east London.

Sabina Nessa death
Jebina Yasmin Islam speaking at a vigil in memory of her sister (Jonathan Brady/PA)

Writing on Twitter, the duchess said: “I am saddened by the loss of another innocent young woman on our streets.

“My thoughts are with Sabina’s family and friends, and all those who have been affected by this tragic event. C”

The message was signed off personally with her initial.

It is understood flowers have been laid on the duchess’s behalf.

In March, the duchess privately visited the memorial to murdered marketing executive Sarah Everard in Clapham Common, south-west London, after the 33-year-old was killed by off-duty police officer Wayne Couzens.

He is due to be sentenced next week.

The duchess’s comment came as Ms Nessa’s family made an impassioned plea for women to “keep safe” as hundreds of mourners prepared to pay their respects at a vigil on Friday.

Jebina Yasmin Islam, Ms Nessa’s sister, broke down as she addressed crowds.

“We have lost an amazing, caring, beautiful sister, who left this world far too early.

Sabina Nessa death
Messages were left among flowers and candles (Jonathan Brady/PA)

“Words cannot describe how we are feeling, this feels like we are stuck in a bad dream and can’t get out of it. Our world is shattered, we are simply lost for words.”

Ms Nessa’s uncle, Shahin Miah, described his niece as “a kind and a open-minded person”, who was “always smiling and helping others”.

He said Ms Nessa’s death has “once again brought to the fore the question of women’s safety on the streets”.

In his statement, he said: “We don’t want what happened to Sabina to happen to anyone else.

“We don’t want any other mother’s chest to be empty or filled with deep sorrow, or to see the tears in the eyes of any father.”

Ms Nessa had been walking to meet a friend at a pub near her home when she was fatally attacked in nearby Cator Park.

Her body was discovered by a member of the public the next day, having been hidden under a pile of leaves, it was reported.

Sabina Nessa's last movements graphic
(PA Graphics)

Both men arrested on suspicion of murder in recent days have now been released pending further investigation, while detectives remain keen to trace a third man captured on CCTV near where Ms Nessa was killed.

In a statement released to the PA news agency, Ms Nessa’s sister said: “I urge everyone to walk on busy streets when walking home from work, school or a friend’s home. Please keep safe.

“I ask you to pray for our sister and make dua (supplication) for her. May Allah grant her paradise.”

The Metropolitan Police issued footage and images of the man they wish to speak to, which shows him walking in Pegler Square on the evening Ms Nessa was attacked.

A 12-second clip shows a balding man wearing a black hooded coat and grey jeans, holding an orange object, looking over his shoulder and pulling at his hood as he walks down a path.

Detectives have also released an image, captured in the same area, of a silver car they believe the man has access to and appealed for anyone who recognised either to contact the force immediately.

Metropolitan Police Assistant Commissioner Louisa Rolfe urged anyone who may know the man to contact them.

Detective Chief Inspector Neil John, from the Met’s Specialist Crime Command, said “an extensive trawl” of CCTV in the area continued and said information on the man’s identity and whereabouts could be “vital” to the investigation.

Friends of Ms Nessa gathered for community rally at the East London Mosque on Friday, ahead of a vigil in her honour.

Sabina Nessa death
Members of the public attend a vigil in memory of Sabina Nessa, and in solidarity against violence against women, at Pegler Square in Kidbrooke (Jonathan Brady/PA)

Halima Begum, whose family knew Ms Nessa, told the PA news agency: “Speaking as a woman and a Londoner from the city’s Bangladeshi community, I’m heartbroken.

“Sabina is related to members of my extended family and everything I know about her speaks of a beautiful, intelligent young woman who had so much life to live, and so, so much to offer in terms of making a positive difference to the people’s lives she touched, not least her family’s and the young children she taught at school.”

Ms Begum urged everyone attending a memorial event on Friday for Ms Nessa to “take care this evening, solidarity to yourself and women across London and the UK – all we can do is hope for no more horrendous instances like this, and the countless others these past few months.”