The 15-year-old was named as Cleon Reid on permission of Old Bailey Judge Geoffrey Grigson as he represented a potential danger to the public.
Reid is described as having short curly hair and was wearing a blue T- shirt, brown over-shirt and blue jeans and trainers.
An inquiry is under way into how the six-foot Reid was able to flee "with ease" from his minder while awaiting trial. He was being held at Orchard Lodge assessment centre,south-east London, under a restriction order on his movements.
He is accused of murdering Ted Howell, 75, allegedly stabbed to death during a burglary at his home in Lewisham, south London in November.
Reid is understood to have been arrested on 16 December and ordered to be detained on remand in the secure care of Lewisham Council. Judge Grigson agreed that Reid's identity - up to now protected under a Children and Young Persons Act order - should be made public after hearing details of the escape two days ago.
Nicholas Wood, prosecuting, told the judge the teenager had been taken to the swimming pool at Crystal Palace sports centre by a social worker.
"He is now on the run and police are understandably extremely concerned."
Terry Munyard, defending Reid, said his client suffered emotional problems and there was fear for his own safety.
Reid, from south-east London, was due to stand trial in June. He apparently escaped while changing, unsupervised by his male supervisor.Reuse content