Cell service hit in Boston following bombings

Shortly after at least two bombs exploded near the Boston Marathon finish line today, reportedly killing at least two people and injuring dozens, cell phone service in the heart of the city was severely disrupted.

An Associated Press report initially claimed, citing an anonymous law enforcement official, that "cellphone service has been shut down in the Boston area to prevent any potential remote detonations of explosives." But AP reporter Peter Svensson said on Twitter at 2:45 p.m. PT that "cellphone problems in Boston are not due to an intentional shutdown" and the wire service was publishing an updated story. AP subsequently reported that service was operating in the Boston area, though cell traffic was heavy in the aftermath of the bombings.

Sprint had previously said its service was spotty because of an overloaded network. "There's no way the network can handle that kind of traffic," Sprint's Mark Elliot told the Boston Globe. Sprint later told CNET it had added additional capacity to its network in anticipation of the marathon and that its service is back to normal.

"Minus some mild call blocking on our Boston network due to increased traffic, our service is operating normally," Sprint Nextel spokeswoman Crystal Davis said. "Sprint did augment capacity on its cell sites along the marathon route in preparation for today's race and voice levels are returning to normal as law enforcement and first responders have cleared out the area as part of their emergency response. We are asking customers to text rather than call to free up lines for emergency personnel."

CNET Executive Editor Jim Kerstetter, a participant in today's Boston Marathon, sent this dispatch after the race:

I was stopped where Commonwealth Avenue goes under Massachusetts Ave., at roughly the 25.5. mark. When we realized what was going on, I was able to use a spectator's phone to leave a message for my wife to tell her I'm safe. After that, service generally went out. I walked home from there (it's a little over two miles to my house) with a woman who lived near me who did have a phone on her, and she was able to send sporadic text messages, including one to tell my wife to not come down to the finish line to meet me and to meet me at home. Service still seems sporadic.

Verizon Wireless provided CNET with a statement saying:

Verizon Wireless has been enhancing network voice capacity to enable additional calling in the Copley Square area of Boston. Customers are advised to use text or email to free up voice capacity for public safety officials at the scene. There was no damage to the Verizon Wireless network, which is seeing elevated calling and data usage throughout the region since the explosions occurred.

Neither T-Mobile nor AT&T immediately responded to CNET's requests for comment, though AT&T tweeted that Boston customers may experience issues with wireless voice and data service due to a spike in network activity. The carrier also asked people in the area to use text messaging and keep non-emergency calls to a minimum.

Many Twitter users, meanwhile, are calling for residents of central Boston to unlock their Wi-Fi routers so that all available bandwidth may be utilized by people trying to locate loved ones.

The twin blasts occurred near the marathon finish line at 11:50 a.m PT.

Addressing the nation from the White House press room later in the day, President Obama said:

The nation will remember Boston in their prayers tonight. Federal officials are mobilizing resources to help. I've notified leaders of both parties; they agree that on days like this, there are no political parties.

Police, firefighters, first responders, and the National Guard responded heroically. We salute all those who responded so quickly and professionally to this tragedy.

We still do not know who did this or why; we still don't have all the facts. We will get to the bottom of this. We will find who did this and we will find out why they did this. Any responsible individuals, any responsible groups will feel the full weight of justice.

Today is Patriot's Day, a day that reflects the freedom Boston has celebrated throughout its history. Boston is a tough and resilient town; so are its people. I'm sure the people of Boston will pull together.

As we get more information, our teams will provide more briefings. We'll find out who did this, and we'll hold them accountable.

Last updated at 3:27 p.m. PT.