Police said he attended Homewood College, Brighton, on Friday (April 7) and at around 10.40am was seen to leave and board a bus bound for the city centre.
He was last seen in the Moulsecoomb area with his elder brother Hassan the following morning, according to police.
A police spokesman said: “Hamza is described as being of Middle Eastern appearance, 5ft 3in, of large build, with brown eyes, a fresh complexion and short black curly hair. He is asthmatic.
“Hamza was last seen wearing a black hooded jacket, black jeans and blue Hiratchi Nike trainers. He is known to frequent fast food outlets.”
PC Mark Green said: “We are concerned about Hamza due to his age. If anyone knows where he is or has any information please contact us.”
If you see Hamza or know of his whereabouts, please contact police online at https://sussex.police.uk/contact-us/response-to-appeal/, email [email protected] or phone 101, quoting serial 501 of 07/04.
Should Hamza appear to be in danger or in need of urgent medical attention, please call 999.
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