WRAPUP 4-FBI arrests 21-year-old National Guardsman for 'criminal' US intelligence leaks
U.S. officials have been hunting for the person responsible, while assessing and seeking to limit damage from the release of the intelligence reports, which reveal purported details of Ukrainian military vulnerabilities and information about allies including Israel, South Korea and Turkey. It is believed to be the most serious security breach since more than 700,000 documents, videos and diplomatic cables appeared on the WikiLeaks website in 2010.