Authorities are investigating a third report of a suspicious letter in D.C. Thursday.
Police and fire are investigating the letter at the Interstate Commerce Commission at 1201 Constitution Ave. NW. It was described as similar to two other suspicious letters found Thursday, but FBI sources said it is not related to those letters.
There have been seven suspicious letters in D.C. this week and several more around the county.
D.C. Police and Fire responded to two reports of suspicious letters Thursday morning -- one at an elementary school in southwest D.C. and another at a restaurant on New York Avenue in the Northwest.
The investigation continues at the northwest restaurant, Osteria Bibiana, at New York Avenue near 12th and H Streets.
Osteria Bibiana, at New York Avenue near 12th and H, was ordered evacuated after the chef received a letter containing a suspicious substance. The general manager there told News4's Erika Gonzalez the restaurant everyone was ordered out around 11:15 a.m. He said a white substance poured out of a letter opened by one of the chefs. That letter was reportedly postmarked from Texas.
Another envelope containing an unknown powder was found at the Amidon Elementary School on Thursday morning, at 401 I Street in Southwest D.C.
The suspicious letter was discovered before the start of the school day. When parents arrived to drop off their children, administrators turned them away, and no students were allowed inside. At 10:45 a.m., Hazmat teams headed into the school to investigate.
At 11:20 a.m, the scene was cleared. No threat was detected.
This is the second day District law enforcement has been on the alert for suspicious powder investigations. On Wednesday, students at the Oyster-Adams School on 19th Street in northwest D.C. were evacuated after a mysterious powder was discovered there. After an investigation, D.C. police determined there was no threat, and school resumed.
News4 obtained a copy of a federal law enforcement bulletin about recent suspicious mailings. From the bulletin:
A series of “white powder letters” were received in the District of Columbia in October, 2010 and May, 2011. Similar letters were received at various locations around the country March 6, 2012 and additional letters may be in the mail system pending delivery. Specially trained response teams are prepared to investigate and collect any suspicious letters.
The letters are postmarked Dallas,Texas and contain a letter with the words AL AQEDA-FBI or similar language and contain a white powder. They are typically addressed using a computer printed label.
District Public Schools have been informed about the letters and have been told to be on the lookout.
Check back for more details on this developing story.