NATO countries are warning Russia that they will retaliate -- in unspecified ways -- if the country continues to fly military aircraft in their airspace.
Russian fighter jets illegally entered Estonian airspace Friday. A senior Estonian official says it's time for NATO forces to consider shooting down the next Russian plane that crosses the line.
A plane carrying European Commission President Ursula von der Leyen was temporarily blocked from landing in Bulgaria due to what Bulgarian authorities say was Russian GPS jamming.