MANCHESTER, England — Police arrested 11 fans at the League Cup semifinal between Manchester United and Manchester City on Wednesday, detaining the same number of hooligans in the last 48 hours as at the first leg.

Police had stepped up searches and patrols before the second leg at Old Trafford, but still had to make the arrests on suspicion of various offenses including public order, affray and criminal damage.

Trouble broke out inside and outside the City of Manchester Stadium when City beat United 2-1 in the first leg and police arrested 18 people last week.

Another 11 fans were detained on Tuesday and Wednesday on suspicion of conspiracy to commit violent disorder after Greater Manchester Police released TV footage of the violence to try and identify some of the troublemakers.