Boston on lockdown

A message calling for citizens of Boston to "Shelter in Place" flashes on a sign on I-93 near the Zakim Bridge in Boston, April 19, 2013.

The Boston area was all but paralyzed as a manhunt continued for Dzhokhar Tsarnaev, one of the two suspects in the Boston Marathon bombing who authorities say killed an MIT police officer and hurled explosives at police in a car chase and gun battle overnight that left his brother, Tamerian Tsarnaev, dead.

Boston Bomb Suspect Search — John Tlumacki/Getty Images

Tensions were high as the search for a second Boston Marathon bombing suspect just about shut down the city. Summer Street in South Boston was vacant of cars at 9:30 a.m.

A lone pedestrian walks along Pearl Street in downtown Boston after mass transit was suspended while a suspect was hunted following bombings near the finish line of the Boston Marathon, April 19, 2013.

Faneuil Hall in downtown Boston, Mass. is seen empty, April 19, 2013.

BAn entrance into Fenway Park is closed after the game between the Kansas City Royals and Boston Red Sox was canceled in Boston, Mass., April 19, 2013.

The Boston Harbor Cruises were shut down on Boston's Long Wharf, April 19, 2013.
Public transportation and most businesses were shut down and heavily guarded by police on Friday.

Gates at Fenway Park are locked after the game between the Kansas City Royals and Boston Red Sox was canceled in Boston, April 19, 2013.

A Boston Police detective searches outside of South Station for suspicious material after two bullets were found outside of a T stop in Boston, April 19, 2013.
South Station was shut down and heavily guarded by police in response to the early morning shootings in Cambridge and Watertown, Mass.

Police are seen standing outside of South Station in Boston, April 19, 2013.
South Station was shut down and heavily guarded with police in response to the early morning shootings in Cambridge and Watertown, Mass.

A view of the deserted Boston Harbor, April 19, 2013.

Armed Boston Maritime Safety Security team members patrol the Boston Harbor, April 19, 2013.

Pigeons hover as no traffic passes on House Street in downtown Boston, April 19, 2013.
Mass transit was suspended while a suspect was hunted following bombings near the finish line of the Boston Marathon.

A pedestrian crosses the intersection of deserted Broad and State Streets, as One International Place towers in the background in downtown Boston, Mass., April 19, 2013.

A virtually deserted Congress Street in downtown Boston, Mass., April 19, 2013.

The streets and sidewalks around Faneuil Hall Marketplace in Boston, Mass., are almost deserted at dinnertime, April 19, 2013 as a call for "shelter-in-place" for Boston and some area communities remains in force.

The usually busy Kenmore Square in Boston, Mass., is virtually deserted at lunchtime, April 19, 2013, during a call for "shelter-in-place" for Boston and some area communities.

A pigeon flies along deserted State Street, as the Custom House hotel towers in the background in downtown Boston, Mass., April 19, 2013.

The streets and sidewalks around the Rose Kennedy Greenway in Boston, Mass., are almost deserted at dinnertime, April 19, 2013.