Five sought over Reker Ahmed attack in Croydon
Police investigating the "brutal attack" on a Kurdish-Iranian asylum seeker in south London are still looking for five males.
Reker Ahmed was beaten and kicked by a gang while waiting at a bus stop in Croydon on Friday night.
A family friend said the 17 year old had been left "black and blue" and "mentally not well" after the assault.
Thirteen people, aged between 15 and 24, have been charged with violent disorder in relation to the attack.
A total of 16 people have been arrested. Three of those will face no further action.
Det Supt Jane Corrigan said "somewhere in the region of 20-30 people who were in the vicinity of the attack... may have had some involvement in the incident".
She said "CCTV enquiries" had identified five people police want to contact "but there is a possibility that this may rise".
Mr Ahmed suffered a bleed on his brain, a fractured eye socket and fractured spine in the attack.
He was visited by his brother Hadi Ahmed on Tuesday who said Reker had not recognised him.
Family friend Abdullah Abdullah, who also saw him in hospital, said the the 17-year-old "was very bad, his face had been smashed very badly".
"He couldn't recognise me as well. Mentally he is not well," he said.
A demonstration by Kurds was held in Croydon earlier.
Rebaz Mohammed, a Kurdish community leader, said the attack "will be with Reker for the rest of his life".
"There's not enough support for asylum seekers who come over... they need help to integrate," he said.
Communities Secretary Sajid Javid, who also attended, said the teenager "came to this country seeking refuge and safety but... he got the exact opposite".
"When something like this does happen we must do everything we can possibly do to apprehend those that were responsible," he said.