A 65-year-old woman arrested on suspicion of murdering a Sydenham DJ has been released without charge, police say.
Luke Jackson, also known as MC Bluetooth, was stabbed at his mother's Pimlico home on December 19 last year.
The 33-year-old was pronounced dead at the scene.
An 18-year-old man arrested at Heathrow Airport on December 21 on suspicion of murder has been bailed until next month.
Another man, 19, was arrested in Paddinton the following day and has also been bailed.
DCI Bonner, said: "I would appeal to anyone who was in the area near Lumley Flats in Pimlico between 5.30pm and 6pm on December 19 to contact us.
"There would have been many people in the area and they may hold vital information into what happened."
Any witnesses or anyone with information is asked to contact the incident room on 020 8358 0200 or call Crimestoppers anonymously on 0800 555 111.
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