UPDATE: 12:50 p.m. -- CNN reports that the all-clear has been given at Senate office buildings after the suspicious packages were removed by authorities.
UPDATE: 7:00 p.m. -- The Associated Press reports that the packages investigated at the Senate were not hazardous. A man was still being questioned in connection with the incident.
A bomb squad was dispatched to the U.S. Capitol building on Wednesday, after a suspicious package was found on the premises.
The Associated Press reports that a suspect is being questioned:
U.S. Capitol police are investigating the discovery of at least two suspicious packages in Senate office buildings and "the individual who delivered them is being questioned," Sergeant at Arms Terence Gainer said on Wednesday.
Gainer said in an email the packages were delivered to at least two Senate offices.
The development comes on the day after a letter mailed to Sen. Roger Wicker of Mississippi was found in two preliminary tests to contain ricin, a potentially fatal poison. The letter was intercepted at an off-site facility where all mail to the Senate is screened.
It was not clear whether there was a connection between the letter and the envelopes.
Other officials said one of the packages had been discovered in the Russell Building, and the second in the Hart office building.
White House press secretary Jay Carney later spoke to reporters, saying there was no indication of a connection between Monday's bombing at the Boston Marathon and the packages or letters.
Meanwhile, an aide to Sen. Carl Levin (D-Mich.) reported that his office in Saginaw, Mich. has been evacuated after staffers reported receiving a suspicious piece of mail.
This story is breaking. Check back for more updates...