Three men aged between 24 and 31 were arrested on suspicion of affray after apparently causing unrest at St Edmund's church, where 350 people had gathered for the festive service.
Monsignor Vincent Harvey told BBC News that the disturbance began with loud voices erupting at the back of the building upon the conclusion of his sermon.
"I was aware of an almighty fight going on, and a panic among the congregation," he said. "Heavy steel chairs were thrown which was an extremely dangerous situation."
Harvey claimed he went to investigate, but was warned by those gathered that it would be too dangerous.
"My main concern was for the safety of the congregation," he said. "Security is not normally an issue, this kind of incident is a very rare occurrence."
The service resumed shortly after the incident, with most of the congregation electing to stay until the end.
The alleged perpetrators have been bailed until Friday (December 30) pending further inquiries.
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