Published Thursday, 12 July 2012
Police are advising the public to avoid the Bogside in Derry (© Pacemaker)
The missiles were thrown in the Westland Street area and at the Derry Walls on Thursday night.
One car was set alight after being hit by a petrol bomb in the Fahan Street area.
Police say no injuries have been reported at this stage.
They are advising the public to avoid the Bogside area "due to current disorder".
They have asked parents to ensure that they know where their children are and what they are doing.
"Any young people involved in this type of activity can expect to face the consequences of their actions - which can range from being taken into custody, taken home to parents and indeed being placed before the courts on criminal charges," a PSNI spokeswoman said.