Bandwidth Issues Down Boston Cell Service, Not Police

Cellphone service in the Boston area is currently experiencing disruptions, following the explosions at the finish line of the Boston Marathon.
Much of the service disruption seems to be due to increased usage. A Sprint representative described the situation to the Boston Globe, saying that "the network is blocking calls because the number of calls coming in exceeds the capacity.”
Verizon released 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."