My theory:
Sniper left a cell phone behind that he is going to call.
Mrs. Fixit's theory:
Sniper left behind a number that leads to one of those anonymous voice mailbox services, (advertising supported things that hook to web freemail) and the like, and the sniper will call in and leave messages, then the bad guy will call in and leave messages.
My guess: Either the sniper or someone who knows who the sniper is -- called the Ponderosa and left a message, saying he wanted to talk on the phone to the Chief of Police of Ashland (what is his name?) And he left a phone number saying, he'd know when to call this number, after they announce during a news conference today when they have the phone line set up and ready to receive his call. Also, for the police to validate to him that the Chief of Police of Ashland will be the one answering -- by mentioning his name during the news conference.
How does that sound?