Police are investigating two incidents of disorder in Cardiff which left two people in hospital.
They happened at about 19:15 BST in Glyndwr Road, Ely, and 20:50 in Tatem Drive, Fairwater, on Tuesday.
Police are linking the two incidents which they said involved a number of young men. One person has potentially life-threatening injuries, another has leg injuries.
Extra officers are patrolling the areas to provide reassurance to residents.