A 15-year-old boy suffered knife wounds after a disturbance in Cardiff.
South Wales Police said that just before 7pm on Sunday July 5 officers were called to an incident at Heol Trelai, Ely.
A 15-year-old boy suffered knife wounds and is receiving hospital treatment.
A police spokeswoman said no arrests have been made and enquiries are ongoing.
They added: "Understandably there is shock and worry within the community when an incident such as this happens.
"Please be reassured that tackling knife crime is a priority for South Wales Police and we are seeing good results."
In the three months since the start of April operation sceptre teams in Cardiff and Swansea have taken £111,000 in drugs off the streets, seized £124,000 in cash, recovered 91 weapons and made 175 arrests.
A spokeswoman said: "These covert teams are out there on the streets making it uncomfortable for anyone who matches the profile of those involved in knife crime.
"Families and communities can play their part in helping to tackle serious violence by taking responsibility for their children and young adults who are on the fringes of criminality or at risk of carrying a knife."
Anyone with information is asked to contact South Wales Police on 101 or Crimestoppers anonymously on 0800 555 111 quoting occurrence *237935.
