It's a city under siege.
A deserted landscape is what the normally bustling streets of Boston looked like after authorities issued the grim warning to everyone: Stay inside and lock your doors.
Massachusetts Governor Deval Patrick said at tha press conference, "We're asking people to shelter in place. In other words, stay indoors with their doors locked, not to open the door for anyone other than a properly identified law enforcement officer."
The historic lockdown came as lawmen hunt the surviving Boston Marathon bomber who is heavily armed and thought to have explosives strapped to his body.
NBC News' Pete Williams reported, "There is further concern that these two men may have had accomplices and that is magnified by the fact that this morning, authorities found another bomb in Boston."
This was the headline in The Boston Globe: "Residents Told To Stay Inside As Hunt Continues."
The New York Times headlines: "Dragnet Shuts Boston."
In addition to Boston, also on lockdown are Watertown, Cambridge, Newton, Waltham, Belmont and Brookline. All are under a so-called "shelter in place" order. An estimated one million people are locked in their homes.
Boston's mass transit system, which handles more than a million passengers a day, is shut down.
Video was shot at 6 a.m., the beginning of the morning rush hour. The city's world-famous colleges have been closed too. Harvard is deserted with a guard at the locked gate.
A sign at a locked-up Starbucks says they are closed.
In Watertown, ground zero for the manhunt, the only people on the streets were law enforcement.
As INSIDE EDITION's Les Trent found out, they're taking absolutely no chances. Trent reported in front of a police tactical unit where an armed police officer aimed his rifle out of the roof of the vehicle at an apartment building. Some of the people who live in the neighborhood were staring out their windows.
Before they searched the bomber's home, authorities were extremely cautious.
A police officer said at a press conference, "There will be a controlled explosion, if you will. It's done out of an abundance of caution. It's done for the safety of the law enforcement officials that are over there before they proceed with a search of the premises."
NBC News correspondent Kerry Sanders was at the center of a dramatic scene in Watertown, where he lied face down on the ground, "The officers started yelling, 'Get down! Get down!' "
INSIDE EDITION's Lisa Guerrero spoke via Skype to Kayla DiPaolo, who was in her Watertown apartment when the shootout erupted right outside.
DiPaolo told Guerrero, "It was so loud, it sounded like it was right next to my head. The explosions, the gunshots. I'm looking at the front door, and a bullet came from the side of the wall mount on the door and went right across from the door frame."
She continued, saying, "I was in hysterics."