It has emerged that there were two separate riots last weekend involving nationalist youths and the PSNI police.
In Belfast, a crowd of up to 200 people clashed with PSNI in the Monagh Road district.
Bottles and glasses were thrown at a police vehicle on patrol in the area and other police vehicles that arrived later were also targeted.
The clashes began when PSNI were accused of harassing residents and quickly escalated. At one point, the crowd attempted to open the doors of the PSNI vehicles, according to reports.
And in Strabane, County Tyrone, over a hundred nationalist youths fought with PSNI in a similar incident.
The PSNI claimed they were investigating a hoax report of a traffic accident when their patrol was set upon.
A crowd of more than 100 quickly gathered in the area and threw stones and bottles.
There were no reports of injury in Strabane, although the PSNI claimed two members were injured in the Belfast incident.