Middlesbrough v Leeds: Twelve arrests after clashes
A dozen people were arrested after violence followed Middlesbrough's home game against Leeds on Saturday.
Officers blamed a "minority of younger people" for trouble which flared outside the Riverside Stadium and the local train station.
The Championship game ended 1-1 after Leeds clinched an injury time equaliser.
No-one was seriously hurt and those arrested have been released pending further inquiries.
Ch Supt John Lyons of Cleveland Police said: "It was disappointing to see some of the behaviour being displayed a minority of younger people, which was unacceptable and we will look to progress criminal proceedings where possible."
All those arrested were male.