POLICE have used CS gas to break up fighting in a Normanton street, which left one officer injured and needing hospital treatment.
A man was arrested on suspicion of assault after fighting broke out in Pear Tree Road, close to the junction with Yates Street, at about 2.30pm on Saturday afternoon.
It followed a peaceful protest by more than 100 people in support of the Palestinian plight in Gaza outside Derby Council House earlier from noon.
After more than an hour of speeches, some of the protestors decided to move through the Pear Tree area.
A Derbyshire police spokesman said: "A group of youths then started walking with the protestors and some of these youths became aggressive, resulting in a fight breaking out.
"Police used CS spray on some of the group to break them up.
"A police officer was injured and taken to Royal Derby Hospital to be treated for his injuries, which were not thought to be serious.
"A man was arrested on suspicion of assault in connection with the incident."
Earlier in the afternoon, the Derby Caribbean carnival parade from Pear Tree was delayed as the incident took place.
Witnesses to the incident or anyone with information on those responsible should call Derbyshire police on 101 or Crimestoppers anonymously on 0800 555 111.
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