Five students were given a "beating" by a gang who attacked them outside a take-away food shop in the early hours.
Police say the students, aged in their early to mid 20s, were minding their own business when they were set upon by a large group of youths outside Rajas takeaway in Great Horton Road, Bradford, at 2.50am on Sunday.
Three of the victims were treated at hospital, one for a broken jaw sustained as a result of being kicked in the head.
Detective Inspector Gerry O'Shea, of Bradford North CID, said: "It was quite a nasty incident and it would certainly have made anyone who was in the area take note. Five students were outside the takeaway when they were set upon by a gang of Asian males for what appears to be no apparent reason. They were given a beating and were all assaulted.
"Four of the students were of African descent and the other was Asian, but I don't know if that is relevant or not. They had walked the short distance from their home to get some food. They are all from different parts of the country and students in Bradford."
Det Insp O'Shea said the area would have been quite busy at the time and appealed for anyone who saw anything to contact police.
He added: "It's quite an isolated incident in that area. It's out of character. We would like anyone who was driving past or who may have seen the incident happen to call us on (01274) 376259."
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