White powder in letter to New York Times

The New York Observer reports that an envelope containing white powder was sent to the New York Times. Police are investigating.*

Here's the email sent to NYT employees:

Folks,

At about 11:30 a.m. today an employee on the 13th floor of our headquarters building in New York opened an envelope addressed to The New York Times. A white granular substance was in the envelope. The New York City police were called and are now on site investigating. The 41st Street side of the lobby is closed but people are able to get in and out of the building. We will keep you updated on any developments.

*UPDATE: NYPD investigators do not think the substance is dangerous, according to the Observer.