Governor Deval Patrick said Boston can expect "heightened vigilence'' on Tuesday, with random security checks on the MBTA and a full law enforcement presence in the city.
"It will not be business as usual,'' Patrick said at a press conference Monday shortly before 9 pm.
The governor and law enforcement officials urged anyone with information to call 1-800-callFBI. He said anyone who sees a suspicious package should report it to authorities. The police will conduct random searches of backpacks and other packages on the T.
"The Boston police department is on emergency deployment... please give us some space around the Copley area as we process this scene,'' said Boston Police Commissioner Ed Davis.
He said the crime scene is in the Copley area.
Copley Station will remain closed Tuesday, but the MBTA was vowing to run normal service otherwise. Exit 22 off the Massachusetts Turnpike, which feeds into Copley Square, will remain closed to traffic on Tuesday. The Boston Public Library at Copley will also be closed.
"It's not going to be easy, simple or regular,'' Patrick said Monday evening, describing the scene commuters and workers will face in Boston.
The MBTA sent out this statement Monday evening:
"Normal Green Line, Orange Line, and Red Line service has resumed. Copley Station, scheduled to be closed on Marathon Monday, remains closed and will continue to be closed Tuesday, April 16, 2013, with trains bypassing the station. 4/15/2013 8:36 PM''
Later, the MBTA tweeted:
"MBTA has every intention of operating regularly scheduled service tomorrow including all Back Bay srvc. Copley Station will remain closed.''
Berklee College of Music announced on Twitter at 9:50 p.m. that the college would be closed on Tuesday.
Emerson College will be closed Tuesday, the college announced late Monday.
Other downtown campuses, such as Suffolk University, Simmons College and the Boston Conservatory, urged students to remain indoors on their websites.
In another sign of the disruption, the NBA cancelled the Celtics-Pacers basketball game scheduled for Tuesday night.
The IRS also announced late Monday that it would provide "individual tax filing and payment extensions for those affected by the Boston tragedy.''