Christopher Ayala, of Washington, started a porch on fire at 56 Broad St., shortly before 4 p.m. Monday, LehighValleyLive reports.
Local firefighters extinguished the blaze in about 15 minutes, officials said.
Ayala was arrested at the scene and subsequently charged with arson, criminal mischief and person not to possess a weapon (a knife), authorities said.
Ayala was lodged in Warren County jail pending a court appearance, officials said.
The incident remains under investigation.
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