Linfield fans are being blamed for an attack on Charlie McKeever’s Pub at Woodhouse Street, Portadown on Saturday evening.
Trouble flared following the Linfield visit to Portadown with a series of what are, at this stage, being seen as sectarian incidents.
According to a witness up to 40 Linfield fans attacked the bar, smashing windows and trying to force their way in through the front doors as terrified staff and customers barricaded themselves in.
Those witnesses say the attack lasted for up to 20 minutes before police arrived on scene. A car is also understood to have been attacked.
It has also been claimed there was serious disorder between the visiting fans and locals in the Tunnel area with some describing the clashes as a riot situation.
At this stage the trouble is thought to have been motivated by sectarianism rather than a clash between rival fans.
It has been suggested the attack may have been in retaliation for an alleged attack on a bar containing Linfield supporters in Belfast carried out by Cliftonville fans.