In light of this afternoon's tragedy at the Boston Marathon, many across the world scrambled to contact loved ones through calls, texts, and social media. Cellular providers had beefed up their networks in advance of the Marathon, but even with the extra capacity the networks became flooded, leading to reports of users being unable to make calls.

There was confusion this afternoon when the Associated Press reported that cell service in the city would be intentionally shut off as police looked to prevent any possible cellular activation of another explosive. However, the news organization basically retracted its original story and found no such shutdown was ordered. The carriers said heavy usage caused connection delays—but service remained available in the city throughout the day.

"Verizon Wireless has not been asked by any government agency to turn down its wireless service. Any reports to that effect are inaccurate," Verizon spokesman Tom Pica told the IDG News Service in an e-mail.

The AP's initial report came from an anonymous law enforcement official, citing an intelligence briefing that supposedly outlined the service shutdown. The FCC later told ABC News it was not aware of any cellular shutdowns, and the news outlet confirmed the same with Sprint, AT&T, and Verizon. (T-Mobile had a similar message for VentureBeat.)

Connection difficulties occurred despite each carrier taking precautions before the race to boost service. Sprint spokeswoman Crystal N. Davis told ABC News that the carrier did "augment capacity on its cell sites along the marathon route" to prepare for the roughly 27,000 runners (plus friends, family, and fans) passing through. T-Mobile also upped its capacity. And after the incident unfolded, these carriers took actions to strengthen their offerings. The message to text instead of call spread throughout the city, Verizon enhanced its network voice capacity in the Copley Square area, and AT&T turned on extra Wi-Fi capacity "for an extended timeframe." ...