Police released new details Tuesday about the events that led to the arrest of four people on immigration charges following a weekend brawl.

The melee involving 19 people erupted Sunday in the Thruway Shopping Center parking lot during an alleged ransom exchange. Police say the relatives of the kidnapping victims told them they were trying to rescue three family members who had been transported from Texas to Connecticut.

Greenwich police say the incident is now being handled by federal immigration authorities, leading some legal experts to believe that the brawl could be part of a larger investigation.