NY Times 
Dec 22, 2012
Top intelligence officials in the New York Police Department met on Thursday to examine ways to search the Internet to identify potential “deranged” gunmen before they strike, Police Commissioner Raymond W. Kelly said.
“The techniques would include cyber-searches of language that mass-casualty shooters have used in e-mails and Internet postings,” Mr. Kelly said in a statement. “The goal would be to identify the shooter in cyberspace, engage him there and intervene, possibly using an undercover to get close, and take him into custody or otherwise disrupt his plans.”
The meeting came almost a week after a gunman killed 26 people, 20 of them children, inside Sandy Hook Elementary School in Newtown, Conn.
There are plans to send officers to Newtown and to scenes of other mass shootings to collect information, Paul. J. Browne, the department’s chief spokesman, said.
Mr. Browne said the potential tactics included creating an algorithm that would search online “for terms used by active shooters in the past that may be an indicator of future intentions.”