New information has been released about suspicious letters containing white powder that have been mailed across the country.

The offices or more than 40 governors across the country have received the letters, including Governor Brian Schweitzer, according to the FBI.

Additional letters have been received at several U.S. Embassies overseas.

So far, the FBI said it does not believe the powder is dangerous, but it still looks suspicious.     

A message was located inside the envelope, which is not being released at this time. The FBI said it is not clear on what the message means.

The white powder has been field screened and the tests have met with negative results.     

The powder has been forwarded to local laboratories and some believe it could be corn starch or flour, but the FBI has asked everyone to be on the lookout for additional letters.     

The Postal Inspection Service is offering a reward of up to $100,000 for information leading to the arrest and conviction of anyone responsible for these mailings.     

Anyone with information on who may be sending the letters is asked to contact the FBI at 1-800-CALL FBI or 1-800-225-5324, the Postal Inspection Service at 877-876-2455 or local law enforcement.

These letters are postmarked Dallas, Texas or North Texas.