The woman, aged in her 60s, was arrested on Tuesday, 8 March, at an address in Westminster on suspicion of assisting an offender.
She was taken into custody at a central London police station where she currently remains.
The arrest marks a significant development in the investigation into the murder of Martine, who was aged 23 when she was killed on 14 March 2008. Her body was found partially covered, surrounded by rubble in a basement of a property on Great Portland Street.
Farouk Abdulhak was quickly identified as a suspect for Martine’s murder. Abdulhak fled the UK within hours of Martine’s death, travelling to Egypt and then on to Yemen.
Detective Chief Inspector Jim Eastwood leads the investigation. He said: “Martine’s family has never given up their fight for justice and in the 14 years since her death they have campaigned tirelessly to keep her in the public consciousness.
“Martine’s family has been informed of this latest development. Though it represents a positive step, there is still much more work for us to do.
“Most importantly, Farouk Abdulhak should be aware that this matter has not, and will not, go away. My team and I will continue to seek justice and use all opportunities available to pursue him and bring him back to the UK. His status as a wanted man will remain and we will not cease in our efforts to get justice for Martine’s family.
“I’m appealing to Farouk Abdulhak directly. Come back to the UK. Come back to face justice.
“Since Martine’s death, her family has shown true determination, together with my investigation team as we want to provide some closure for Martine’s family.”
Police launched an investigation after Martine’s friends reported her missing to police on 15 March 2008.
Martine had been out celebrating finishing her end of term exams with her friends at the Maddox nightclub in Mayfair – she left them, in the company of Abdulhak, at around 02:00hrs on 14 March 2008.
On 16 March 2008, officers making enquiries to trace her visited the residential block where Abdulhak lived on Great Portland Street in Westminster, where they discovered her body at about 10:30hrs. Attempts had been made to conceal her beneath rubble.
A post-mortem examination gave her cause of death as compression to the neck. She had also been raped.
An inquest at Westminster Coroner’s Court on 24 November 2010 recorded a verdict of unlawful killing.
Anyone with any information that could assist the investigation is asked to contact the incident room on 020 8358 0300. You can also contact the independent charity Crimestoppers anonymously on 0800 555 111.