Posted: 8:08 PM President Barack Obama says the Senate's opposition to a bill that would have expanded background checks for gun buyers marks a "shameful day" in Washington.

Posted: 11:40 AM The U.S. Secret Service says it has intercepted a letter addressed to President Barack Obama that contained a "suspicious substance."

Posted: 10:50 AM The hospital calls it a "terrible mistake" and is extending "deep apologies" to the family. It also is offering counseling to employees of the linen service.

Posted: 8:11 AM The exhaustive, yearlong investigation by the Senate Armed Services Committee focused on costs and burden-sharing as the United States spends more than $10 billion a year to back up the U.S. military presence overseas.

Posted: 7:59 AM A day after the bombings, runners head back downtown to receive their marathon medals.

Posted: 7:07 AM A bomber may have been seen amid the Boston Marathon revelers carrying an unusually heavy nylon bag, weighed down with shrapnel-packed explosives, the FBI has suggested.

Posted: 7:06 AM President Barack Obama has aimed to be both visible and cautious in his response, declaring the attack an "act of terror" while warning the nation against jumping to conclusions.

Posted: 7:02 AM Perhaps helping explain Democrats' problems, an AP-GfK poll this month showed that 49 percent of Americans support stricter gun laws.

Posted: 6:59 AM On Tuesday, American and sister airline American Eagle canceled 970 flights and delayed at least 1,068 more by early evening, according to flight-tracking service FlightAware.com.

Updated: 5:03 PM Authorities investigating the deadly bombings at the Boston Marathon have zeroed in on a man seen on surveillance video near the site of the attack.

Updated: 6:40 AM Unlike with the Boston Marathon bomber, police have a suspect in mind as they try to determine who mailed a letter to Sen. Roger Wicker that tested positive for poisonous ricin, a Senate colleague said.

Posted: 9:57 PM Federal agents zeroed in Tuesday on how the Boston Marathon bombing was carried out.

Posted: 9:47 PM - Arkansas plans to put prisoners to death with a drug that experts say has never been used in a U.S. execution.

Posted: 9:44 PM Senate Majority Leader Harry Reid says a letter containing ricin or another poision was sent to the office of Sen. Roger Wicker of Mississippi.

Posted: 11:44 AM President Barack Obama says the explosions at the Boston Marathon are being investigated as an act of terror, although authorities still don't know who is responsible.

Updated: 1:45 PM The boy who was killed in the Boston Marathon bombings was remembered by neighbors Tuesday as a vivacious 8-year-old who loved to run and climb.

Updated: 10:24 AM Over the next week, she pieced together one horrifying detail after another. She went online and tried to confront the three boys she had known since junior high who she believed had done it.

Posted: 5:31 AM Republican opposition is growing to a bipartisan Senate plan for expanding background checks for firearms buyers, enough to put the proposal's fate in jeopardy.

Updated: 5:33 AM Obama, speaking from the White House late Monday, pointedly avoided using the words "terror" or "terrorism," saying officials "still do not know who did this or why."

Updated: 1:47 PM With more than 30 marathons this weekend and big events on the horizon, officials around the world are looking at security efforts in the wake of the fatal bomb blasts that shook Boston's race.

Updated: 5:33 AM It dawned chilly, clear and blue, a parsimonious but perfect serving of New England springtime that — because it came on the third Monday in April — unquestionably called for a celebration.

Posted: 8:48 AM A grand jury about to be seated in eastern Ohio will investigate whether other laws were broken in the case of a 16-year-old girl raped by two high school football players last year.

Posted: 8:46 AM Thousands of people are expected to join an unofficial counterculture holiday celebrating marijuana in Colorado and Washington this coming weekend, including out-of staters and even packaged tours.

Posted: 8:10 AM As Congress readies for a drawn-out immigration debate, an expanding network of Republican fundraisers is pressing for a path to legal status for millions of immigrants living in the United States illegally.

Updated: 8:06 AM A bipartisan group of senators is almost ready to share with colleagues and voters an immigration overhaul crafted over several months.