Reward offered in hunt for Texas anthrax hoax mailer

The United States Postal Inspection Service, in conjunction with the FBI, has offered a $100,000 reward to aid in solving the mystery behind a string of white powder-filled letters mailed across north Texas.

The powder in the 25 envelopes has so far not proven to be toxic, reports. The letters have been sent to businesses, mosques and churches in 11 north Texas cities and are believed to contain references to terrorism.

The letters are said to contain a reference to al-Qaeda.

"The message is not articulated well," Mark White, an FBI spokesman, told "We just don't know what it is the person is trying to tell us."

Federal officials told that they believe the person behind the letters may also be responsible for as many as 225 similar letters that have been mailed both nationally and globally. Those letters were mailed in 2008 to U.S. governors and embassies.

The public is not at risk from the letters, postal authorities contend, but the cost of shutting down businesses to respond to the hoaxes is growing.

Despite the white powder in the envelopes being non-toxic, punishment for such a hoax is up to five years in prison per letter. Officials have said that this latest letter sender is probably a lone person, as such hoaxes are historically perpetrated by loaners.