But in the case of Orlando shooter Omar Mateen, the apparent lone wolf was a known quantity to the FBI. FBI counter-terrorism officials “pursue all possible leads and once that’s been exhausted, it’s closed”, said Erroll Southers, a former FBI counterintelligence and terrorism agent. “What this illustrates is the difficulty in trying to identify people who would do things like Mr Mateen did today,” Southers said. Related: Orlando nightclub shooter Omar Mateen was known to FBI, agent saysRon Hopper, the FBI special agent on scene in Orlando, told reporters on Sunday afternoon that the bureau had on three occasions in 2013 and 2014 interviewed Mateen. US officials have for years warned that so-called “lone wolf” terrorists, unconnected to established and monitored extremist groups, are notoriously difficult to identify in advance of an attack.

Source: The Guardian June 12, 2016 22:18 UTC