A man arrested in connection with the disappearance of Hertfordshire University student Joy Morgan was questioned on suspicion of murder, police have confirmed.
The 40-year old from London was released under investigation while inquiries continue.
Joy, who turned 21 on Tuesday, was last seen on Boxing Day at a Christmas celebration at her church in Ilford, east London.
She made WhatsApp contact with university coursemates the following day and was reported missing on February 7.
Video footage of her dancing with friends at the church event has been released by Hertfordshire Police.
Detective Chief Superintendent Karena Thomas appealed to the public for any more information about the trainee midwife’s whereabouts.
She described Miss Morgan as a “focused and determined” student and said he disappearance was “completely out of character”.
Ms Thomas added: “At this stage we have to consider she may have come to harm.”
The officer described the investigation as “complex” and said: “To gather a full picture of Joy’s life is a difficult jigsaw to piece together.”
Police are particularly interested in hearing from anybody who may have seen the student in a distinctive red and black Honda car that she regularly took lifts in.
Miss Morgan has links to Ilford, Battersea and Cricklewood in London, as well as Bedfordshire.
She is described as slim, around 5’5” tall, with Afro hair that she regularly covers with a scarf, and glasses.
Her family issued an appeal earlier this week as they marked her 21st birthday without her.
They said in a statement: “We love you, we miss you.
“Wherever you are, text or call so that we know you are alright.
“It doesn’t matter what has happened. Just come home.”