One man was arrested after a flare was thrown at spectators at today's Sunderland v Portsmouth game.
It is believed a flare was thrown from the away supporters' area in the upper tier of the North Stand at the Stadium of Light during the first-half of the game.
The smoke from the flare could be seen behind the goal in the North Stand.
Northumbria Police confirmed a man was arrested and taken into police custody.
Northumbria Police Superintendent Sarah Pitt said public safety is paramount and that police worked with the club to quickly take action following the incident.
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After the flare was thrown play had to be stopped for around four minutes while police dealt with the incident.
Police entered the area, with Sunderland fans pointing the finger at the away fans above them.
After the short delay the referee restarted the game with the score currently 1-1.
Earlier this month, SAFC owner Stewart Donald said he was "distraught" after Black Cats fans said they had coins, bottles flares thrown at them by Coventry City supporters when the two sides played each other at the Stadium of Light on Saturday, April 13.