FBI investigates threatening letter to Cottage Grove business
The Cottage Grove Renewal by Andersen location was among 13 Twin Cities area businesses to receive threatening letters containing a nontoxic white powder substance in recent days, according to the FBI.
The agency is investigating the mailings, which occurred between Dec. 31 and last Thursday, Ralph Boelter, special agent in charge of the Minneapolis FBI office, said in a news release. The Cottage Grove Renewal by Andersen received the letter Thursday, said Maureen McDonough, director of corporate communications for Andersen Corp. It was turned over to authorities.
"There were several other letters that had been received, so we were on the lookout," McDonough said.
Other Renewal by Andersen locations received letters, as did Home Depot stores, including in Woodbury and Hastings.
According to the FBI, the agency is in possession of the threatening letters and the envelopes. The return address on each envelope is identical. The letters received by the businesses are exactly the same letter that appears to have been photocopied.
The white powder substance present in the first 12 letters was analyzed by the Minnesota Department of Health lab in St. Paul. The substance in each letter was identified as sodium bicarbonate, and is not toxic or otherwise dangerous.
The substance in the letter received by the Cottage Grove Renewal by Andersen had not been analyzed when the FBI announced that the cases were under investigation.