Four people suspected of involvement in the gang-style shooting of a Croydon student were re-bailed on Monday.
Ricardo Cox, 20, of Mitcham Road, was gunned down on November 26, 2008 as he returned home from Croydon with his brother.
So far eight people have been arrested for his murder but on Monday that number dropped to four, as half were released without charge.
Mr Cox was shot twice by what police say is a distinctive .22 calibre gun, probably a revolver.
Police want anyone who can help to call 020 8721 4805 or Crimestoppers on 0800 555111.
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