On April 29, the self-proclaimed government of the Donetsk People’s Republic announced it had expelled seven Western aid workers accused of spying. But that was a lie. Only the five European aid workers detained were let go, while two Americans — a doctor and a humanitarian worker with the International Rescue Committee — were kept for nine more days. During that period, a network of aid groups and international organizations worked quietly behind the scenes to secure their release. They were finally freed on May 8.

What’s never been reported is that during those tense days, Kerry personally intervened and raised the issue over the phone with Russian Foreign Minister Sergei Lavrov, asking him to use Moscow’s influence over the Donetsk separatists to secure the release of the two Americans, a senior administration official told us. Several diplomatic sources told us that Lavrov came through, making it clear to the Donetsk leadership that holding the Americans longer was not a good idea.

http://www.bloombergview.com/articles/2015-05-19/kerry-helped-free-u-s-spies-trapped-in-ukraine