Police are investigating a suspicious powder in an envelope opened by an employee at a lower Manhattan office building near the World Trade Center, sources said.
The employee was exposed to the powdery substance while opening the letter shortly before 7:30 p.m. Tuesday.
Police were called to a mail room at 225 Liberty Street, formerly Two World Financial Center, across the street from the World Trade Center.
Investigators have isolated the envelope and tests are being conduct, law enforcement sources said.
The employee is being evaluated by EMS. His or her condition wasn't immediately known.
