Police were called after witnesses said the man had been sharpening the knife and "acting erratically" at the pool bar in the Minerals Hotel shortly before 2 p.m. Saturday, March 9.
He'd also apparently told an employee that he has PTSD.
The first officer there cleared the area after finding him, township police said.
An off-duty officer and backups from surrounding towns quickly joined him, they said.
The man refused to cooperate, pulled the knife but at one point dropped it and was immediately seized, police said in a release.
He was taken by ambulance in custody for an evaluation at a local hospital.
Although no charges were immediately filed, police on Monday said the possibility was still "under review."
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