Miss Savchenko, 35, was exchanged for Alexander Alexandrov and Yevgeny Yerofeev, two members of the Russian special forces, in a hurried swap on the tarmac of Rostov on Don airport, in southern Russia, on Tuesday afternoon.
The helicopter pilot and army officer was on board a plane back to Ukraine by early afternoon, a source close to the exchange said.
The exchange follows a two-year diplomatic impasse during which Petro Poroshenko, the Ukrainian president, accused Vladimir Putin of using Miss Savchenko as a hostage to exert pressure on Kiev over the war in east Ukraine.
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