Staffers at a number of local Senate offices around the country reported receiving suspicious mail on Wednesday, shortly after letters testing positive for the powerful poison ricin were intercepted before reaching the Capitol Hill office of Sen. Roger Wicker (R-Miss.) and the White House.
Maxine Park of the Arizona Republic reported that home offices of Arizona Sens. John McCain (R) and Jeff Flake (R) were the latest to report the scares:
The Associated Press reported that Flake's office was evacuated and that the letters are now being investigated.
Staffers at the Saginaw, Mich. office of Sen. Carl Levin (D-Mich.) were also evacuated on Wednesday, after telling authorities that they'd received a "suspicious-looking letter."
On Tuesday, a letter addressed to Wicker was flagged at an off-site Capitol mailing facility, where it repeatedly tested positive for ricin. It was later sent off to a Maryland lab for additional testing.
On Wednesday, a letter addressed to President Barack Obama and tainted with the same poison was caught at a facility away from the White House. The Secret Service later confirmed that it had tested positive for ricin.
Authorities have said that there is currently no indication of a connection between Monday's bombing at the Boston Marathon and the suspect mailings.
UPDATE: 2:45 p.m. -- NBC Dallas-Fort Worth reports that authorities have been called to the Dallas office of Sen. John Cornyn (R-Texas) to investigate a suspicious piece of mail:
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