The shelter-in-place warning to the residents of Boston spread throughout social media Friday as Boston police continue the massive manhunt for the second man suspected in the Boston Marathon bombings. It began Thursday night, and officials quickly locked down the city, halting trains, taxis and local businesses. One suspect was killed in a shoot-out with police.

As area residents, like Kathy O'Reilly, awoke to the news, they quickly turned to social media for the latest updates.

"We got the first reverse 911 call at 6:30 this morning telling us the school was closed due to the MBTA shutdown," she said. "We immediately called our kids and they had already received text messages and Facebook updates from the school. Our kids both attend college at Suffolk University. Suffolk has done an awesome job keeping all parents and students updated via their Facebook page."

O'Reilly, who lives north of Boston, has in turn been sharing the information she gets on her Facebook page, while also checking on her friends who live in the Watertown area, where police have focused the manhunt. "Colleagues and friends live in Watertown, so I'm also following live news coverage this morning from their Facebook pages since they're in the middle of everything."

Other residents are following Twitter for the latest news and warnings. The Boston Police tweeted continuously throughout the investigation and posted a tweet early this morning to warn residents in Watertown to stay indoors: