***UPDATE 3: Fox News is now saying “BREAKING NEWS: BOSTON POLICE SAY NO ARREST IN BOMB CASE AMID CONFLICTING NEWS REPORTS” but they still haven’t updated their main article.
UPDATE 2: Fox News has changed their homepage to reflect that there are ‘conflicting reports’ about whether an arrest has been made or not. They haven’t changed their story yet though.
UPDATE: Fox News is reporting an arrest has indeed been made:
Investigators have arrested a suspect in the Boston Marathon bombing, a federal source confirmed to FoxNews.com.
The suspect was seen on surveillance footage and showed a young man carrying – and perhaps dropping – a black bag at the second bombing scene at Monday’s Boston Marathon. The camera at Lord & Taylor, located directly across the street, has given investigators clear video of the area, according to the unnamed official.
“The camera from Lord & Taylor is the best source of video so far,” said Dot Joyce, a spokeswoman for Boston Mayor Thomas M. Menino told the Boston Globe. “All I know is that they are making progress.”
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They aren’t saying much, but are confirming that they have identified a suspect:
CNN – Investigators believe they have identified a suspect in the Boston Marathon bombings, a source who has been briefed on the investigation told CNN’s John King exclusively.
The breakthrough came from analysis of video from a department store near the site of the second explosion. Video from a Boston television station also contributed to the progress, said the source, who declined to be more specific but called it a significant development.
A little more info is in the video: