SHEBOYGAN, Wis. (WHBL) - Pigeon River School was locked down for about a half hour Wednesday afternoon while police searched the neighborhood for a man with a knife.  The Sheboygan Police Department said that around 1pm, they responded to a woman being assaulted in the area near the school.  Officers learned a 19 year old man and 20 year old woman had been arguing, and it escalated to the point where he was battering her and threatening her with a knife.  He fled into the woods near Pigeon River trail when witnesses heard the woman screaming for help.  The suspect was arrested after a search and is being held in the county jail.