Under Bloomberg, Commissioner Kelly also revamped New York City's Police Department into a world-class counter-terrorism operation, operating in conjunction with the CIA. Prior to the September 11, 2001 attacks there were fewer than two dozen officers working on terrorism full-time; ten years later there were over 1,000. One of Kelly's innovations was his unprecedented stationing of New York City police detectives in other cities throughout the world following terrorist attacks in those cities, with a view to determining if they are in any way connected to the security of New York. In the cases of both the March 11, 2004, Madrid bombing and the July 7, 2005 London bombings and July 21, 2005 London bombings, NYPD detectives were on the scene within a day to relay pertinent information back to New York. An August 2011 article by the Associated Press reported the NYCPD's extensive use of undercover agents (colloquially referred to as "rakers" and "mosque crawlers") to keep tabs, even build databases, on stores, restaurants, mosques. and clubs. NYPD spokesman Paul Browne denied that police trawled ethnic neighborhoods, telling the AP that officers only follow leads. He also dismissed the idea of "mosque crawlers," saying, "Someone has a great imagination."