FBI investigating suspicious letters with white powder sent to D.C.-area schools

(CBS/WUSA/AP) WASHINGTON - Twenty-nine suspicious letters containing white powder were reported at Wash., D.C. schools Thursday, appearing to have been mailed from the Dallas area, officials say.

According to officials it's believed to be part of a pattern they are seeing across the country. None of the letters have been determined to be hazardous, reports CBS affiliate WUSA.

The letters have the same characteristics as mailings under investigation by the FBI and postal inspectors in Dallas.  The local FBI is part of the investigation but will not confirm any connection between the D.C. letters and the last letters received at Dallas-Fort Worth area schools and churches, though they have confirmed that the letters were postmarked from Dallas. A suspect has not been arrested in connection with those Dallas-Fort Worth area letters, reports the station.

FBI officials have had everything sent to a laboratory for analysis in Quantico, Va., according to WUSA.

The first D.C. letter was reported around noon Thursday. The city has more than 100 public schools and another 52 charter schools with 93 campuses. Mayor Vincent Gray condemned the mailings as "a dastardly act."

Some of the schools were "partially evacuated" according to D.C. fire officials. No injuries were reported at any of the schools.