2:25 PM -- BOSTON (AP) - Boston police say two people were killed and 23 people were hurt when a pair of bombs exploded near the finish line of the Boston Marathon.
The blasts shattered the end of the race Monday, sending authorities out on the course to carry away the injured while stragglers in the 26.2-mile race were rerouted away from the smoking site.
3:00 PM -- Boston race draws 86 from Oklahoma
OKLAHOMA CITY (AP) - More than 80 Oklahoma runners were registered to run in the Boston Marathon, where two explosions rocked runners and spectators near the finish line after the race.
According to the race's website, 86 runners in Monday's race listed Oklahoma as their home state.
It wasn't known whether any Oklahomans were injured.
About three hours after the winners crossed the finish line, there was a loud explosion near a photo bridge that marks the finish line. Another explosion rang out a few seconds later.
3:30 PM -- FAA orders no-fly zone over Boston explosion site
WASHINGTON (AP) - The Federal Aviation Administration is warning pilots that it has created a no-fly zone over the site of two explosions at the annual Boston marathon.
The agency said in a notice issued Monday about an hour after the explosions that a no-fly zone with a 3.5-mile radius has been created over 811 Boylston Street. The zone is limited to flights under 3,000 feet in altitude, which is lower than most airliners would fly except when taking off or landing.
The notice says the no-fly zone is effective immediately and will remain in effect until further notice. Pilots planning flights were urged to call their local flight service station.
3:35 PM -- Security beefed up worldwide after Boston blasts
LOS ANGELES (AP) - Police in Los Angeles, New York City, London and other cities worldwide are stepping up security following explosions at the Boston Marathon.
Los Angeles County Sheriff's spokesman Steve Whitmore says the department has opened an emergency operations center, increased patrols for transit and other critical areas including the Los Angeles Dodgers game Monday night
Chief NYPD spokesman Paul Browne said Monday that critical response teams are deployed around the city. Officials are stepping up security at hotels and other prominent locations.
British police also say they are reviewing security plans for Sunday's London Marathon. It's the next major international marathon. A London Metropolitan Police spokesman says police are working with marathon officials to review security plans.
3:46 PM -- DHS providing 'whatever assistance' needed
ALICIA A. CALDWELL, Associated Press
WASHINGTON (AP) - Homeland Security Secretary Janet Napolitano is directing her agency to provide "whatever assistance" necessary in the wake of two explosions near the finish line of the Boston Marathon.
About two hours after the winners finished the race there were two explosions near the finish line Monday, killing at least two people and injuring as many as 23 others.
Boston Police and federal authorities are trying to determine what happened.
4:01 -- Boston police: 3rd explosion at library
JIMMY GOLEN, AP Sports Writer
BOSTON (AP) - Boston police say there's been a third explosion in the city, following two blasts near the finish line of the Boston Marathon that killed two people and injured many others.
Police Commissioner Edward Davis says authorities aren't certain that the explosion that occurred more than an hour later at the JFK Library was related to the other blasts, but they're treating it as if it was.
Davis says there are no injuries stemming from the third explosion. The total numbers of casualties from the other blasts isn't known.
Davis urged people to stay indoors and not congregate in large groups.
Police say they received no information before the explosions to indicate they were coming.
4:22 -- Boston blast heightens senses in Oklahoma
OKLAHOMA CITY (AP) - The Oklahoma Highway Patrol says there have been no threats or heightened security in the aftermath of a bombing at the Boston Marathon - but that senses are heightened.
Trooper Betsy Randolph says the Boston bombing focuses attention on the scheduled April 28 Oklahoma City Memorial Marathon. Randolph says authorities have always focused on security measures around the April 19 anniversary of the Oklahoma City bombing and during the marathon.
Oklahoma City Police Capt. Dexter Nelson says police have always increased security for the race and adds both on-duty and off-duty officers for the race.
Oklahoma City Mayor Mick Cornett says there are currently no plans to call off this year's Oklahoma City marathon - but said events will be monitored daily.
4:23 -- Full Justice Dept. resources probing Boston bombs
FREDERIC J. FROMMER, Associated Press
WASHINGTON (AP) - Attorney General Eric Holder has directed the full resources of the Justice Department be deployed to investigate the bombs that exploded at the Boston Marathon.
A department official said Holder has spoken with FBI Director Robert Mueller and with Carmen Ortiz, the U.S. attorney for Massachusetts. The official said Ortiz's office was coordinating the department's response with the FBI and other federal, state and local law enforcement authorities.
The official spoke on condition of anonymity because she was not authorized to speak on the record.
Two bombs exploded near the marathon's finish line on Monday, killing two people and injuring many others. A senior U.S. intelligence official said two other explosive devices were found nearby. A third explosion followed at the JFK Library in Boston.
4:25 -- Secret Service expands security at White House
WASHINGTON (AP) - The Secret Service says it has expanded its security perimeter at the White House following the explosions at the Boston Marathon.
Secret Service spokesman Ed Donovan says the measure was taken "out of an abundance of caution." He says it is not unusual to expand or contract the security perimeters.
Shortly after the explosions Monday, Secret Service shut down Pennsylvania Avenue outside the White House, cordoning off the area with yellow police tape. Several Secret Service patrol cars also blocked off the entry points to the road.
The White House was not on lockdown and tourists and other onlookers were still able to be in the park across the street from the executive mansion.
4:41 -- Phone companies: Cellphone use heavy, but still operating in Boston after explosions
WASHINGTON (AP) - Cellphone companies say service is operating in the Boston area, but with heavy traffic following of the explosions at the Boston Marathon.
A law enforcement official, citing an intelligence briefing, said cellphone service had been shut down Monday in the Boston area to prevent any potential remote detonations of explosives.
But officials with Verizon Wireless and Sprint Nextel said there had been no such requests.
Sprint spokeswoman Crystal Davis said: "Minus some mild call blocking on our Boston network due to increased traffic, our service is operating normally."
Two people were killed and scores injured when two explosives detonated near the finish line of the marathon.
5:01 PM -- Boston police commissioner: JFK Library fire doesn't appear to be related to race explosions
BOSTON (AP) - Boston police commissioner: JFK Library fire doesn't appear to be related to race explosions.
5:11 PM -- Boston police: No one in custody in race blasts
JIMMY GOLEN, Associated Press
BOSTON (AP) - Boston police say no suspect has been taken into custody in connection with the explosions near the finish line of the Boston Marathon.
Police Commissioner Edward Davis also says that the fire at a library a few miles away and more than an hour later doesn't appear to be related to the explosions at the race on Monday. He says the fire may have been caused by an incendiary device.
Authorities say the blasts killed two people and injured at least 73.
Police say it's too early to get into specifics about the nature of devices or whether shrapnel was involved.
5:24 PM -- Obama: 'We will find out who did this'
WASHINGTON (AP) - President Barack Obama, responding to the explosions at the Boston Marathon, says the United States does not know "who did this or why" but vowed that whoever is responsible "will feel the full weight of justice."
He said: "We will find out who did this and we will hold them accountable."
Obama made his remarks Monday evening from the White House about three hours after two explosions detonated near the marathon's finish line. At least two people were killed and 50 injured in the blasts.
Obama has been in touch with federal law enforcement and Massachusetts officials in the aftermath of the explosions.
The Secret Service reacted cautiously to the blasts, expanding the security perimeter around the White House.
8:45 AM -- Mass. gov: No unexploded bombs at Boston Marathon
JIMMY GOLEN, Associated Press
BOSTON (AP) - Massachusetts Gov. Deval Patrick says no unexploded bombs were found at the Boston Marathon. He says the only explosives were the ones that went off Monday.
Three people were killed, including an 8-year-old boy, and more than 150 injured by two explosions just seconds apart near the finish line Monday.
Authorities are appealing to the public for amateur video and photos that might yield clues to who carried out the bombing.
11:00 AM -- Security heightened at Boston airport after blasts
BOSTON (AP) - Boston's Logan Airport has heightened security the day after two bombs exploded at the Boston Marathon.
One flight was returned to the gate and rescreened, while another was held after landing so authorities could inspect the baggage.
A US Airways spokesman says the Transportation Safety Administration asked that Flight 1716 from Philadelphia be parked remotely when it landed and the baggage inspected. Passengers were taken to a building away from the terminal during the inspection while luggage was unloaded and screened.
United Airways Flight 636 to Chicago was returned to the gate and passengers sent back through security screening at the request of the crew while the aircraft was swept. A United spokeswoman did not say why.
The TSA didn't immediately return calls seeking comment.
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