Crews respond to mailroom incidents at Maryland government buildings.
Two packages "flared up" Thursday when they were opened at Maryland state government buildings, prompting the evacuation of approximately 300 state employees.
Two other suspicious packages were discovered in the distress, though one was found to be a toner cartridge; the other laptop batteries, the Associated Press reported.
The first suspicious packages were discovered in Anne Arundel County at the Jeffrey Building on Francis Street in downtown Annapolis and the Harry Hughes Department of Transportation Building in Hanover.
The ATF and FBI responded to the scenes with explosives experts.
A public information officer in Annapolis said a device went off at about 12:25 p.m. when someone opened a package in the Jeffrey Building, where mail for Gov. Martin O'Malley's office is routinely checked. The package was described as being the size of a book and was addressed to O’Malley. It also had holiday postage stamps on it.
Sources said that when the package was opened in the government mailroom it "flared up."
Maryland State Police spokesman Greg Shipley said the package was opened and "there was an issuance of smoke and a smell." No explosives have been found, Shipley said. He said the person who opened the package suffered "singed fingers" but refused further medical treatment.
Shipley said there was no damage to property in the room. Employees re-entered the building at approximately 2:30 p.m. after the building was declared safe.
The same thing happened at about 12:45 p.m. when a package addressed to the Maryland Department of Transportation -- and including an undisclosed return address -- was opened in the Hughes building. The incident occurred on the fourth floor of the Maryland Department of Transportation headquarters.
Shipley said that in this incident, the person who opened the package dropped it as smoke came out. Shipley said there was a "sulfur-type smell." The person who opened that package and three people who were nearby were taken to a hospital as a precaution.
Sources said the devices were designed to ignite rather than explode. The devices are similar to devices sent out five or six years ago to governors around the country. They were inside a small shipping box.
The Maryland Emergency Management Agency said one of the packages looked like a book-mailer.
State government officials shut down all mail operations at all state agencies. Local governments and colleges were notified.
D.C. Councilman Phil Mendelson said a D.C.-wide alert was sent out to shut down all D.C. government mail operations for the time being, according to NBC Washington's Tom Sherwood.
The University of Maryland also sent alert out ot the university community saying not to open any mail until advised.
The Jeffrey Building houses the Executive Office of the State of Maryland, the Governor's Office of Homeland Security, the State Planning Office, the Secretary of State's office and Veterans Affairs.
An FBI spokesman said a package investigated late Thursday afternoon at a state office building in Baltimore was a box of laptop computer batteries. Another package -- discovered at about 3:30 p.m. at the Clarence M. Mitchell Jr. Courthouse in downtown Baltimore -- also was investigated, Baltimore police spokesman Anthony Guglielmi said. It turned out to be an ink cartridge.
A suspicious package at Dulles International Airport in Virginia caused the closure of the United ticket counter and four baggage carousels for more than two hours before it was determined to be harmless.
Stay with NBCWashington.com for more information.