US deploys over 1000 spies for Olympic security

The United States has assigned more than 1,000 spies to the Olympic security as part of a highly classified effort to protect the Rio 2016 Summer Games and American athletes and staff.

Hundreds of analysts, law enforcement and special operations personnel are already in Rio de Janeiro, according to an NBC News review of the highly classified report on U.S. intelligence efforts.

In addition, more than a dozen of highly trained Navy and Marine Corps commandos from the U.S. Special Operations Command are working with the Brazilian Federal Police and the Navy.

The U.S. military has also placed larger military units on call in case any rescue or counterterrorism operation is needed.

The classified report outlines an operation that encompasses all 17 U.S. intelligence agencies, including those of the armed services, and involves human intelligence, spy satellites, electronic eavesdropping, and cyber and social media monitoring.

Areas of cooperation include vetting 10,000-plus athletes and 35,000-plus security and police personnel and others; monitoring terrorists' social media accounts; and offering U.S. help in securing computer networks.

"U.S. intelligence agencies are working closely with Brazilian intelligence officials to support their efforts to identify and disrupt potential threats to the Olympic Games in Rio," said Richard Kolko, a spokesman for National Intelligence Director James Clapper.

The U.S. is one of the 51 countries supplying intelligence to the Brazilian counterterrorism effort.