Up to 70 people were involved in a series of mini-riots targeting police and police vehicles in Derry city this afternoon.
The disturbances began shortly before 3 o'clock when police were attacked as they attempted to speak to the organisers of what is believed to be an illegal parade.
A police vehicle, which was in the vicinity of the city cemetery at the time, came under a sustained attack during which petrol bombs, paint, bottles, stones and other missiles were thrown.
General disturbances then broke out across the city, involving up to 70 people, but no-one was injured in the riots.
Two youths, aged 15 and 16, were later arrested on suspicion on being in possession of petrol-bombs.
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