Sen. Carl Levin added his regional office in Saginaw, Mich., to the list of places that must review suspicious-looking letters on Wednesday.
Mr. Levin, Michigan Democrat, said a staffer at the office did not open the letter and followed proper protocols by “alerting the authorities, who are now investigating.”
“We do not know yet if the mail presented a threat,” Mr. Levin said on his website. “I’m grateful for my staff’s quick response and for government personnel at all levels who are responding.”
Although it may amount to nothing, Mr. Levin’s announcement shows that wariness around senators’ mail extends beyond Washington.
In the nation’s capital this week, authorities have responded to suspicious letters to the White House and Sen. Roger Wicker, Mississippi Republican, that may be tainted by poisonous ricin.
Each of the letters was screened at a remote site before reaching an actual office.
White House spokesman Jay Carney referred specific questions about the letters to the FBI, which has indicated there is no indication the letters are connected to the explosions at the Boston Marathon on Monday.