MOSCOW, May 20. /TASS/. More than ten blasts were heard in Ukraine’s capital Kiev in the early hours of Saturday, while the city’s air defenses were engaging unknown targets above it, eyewitnesses have told TASS.

"It’s noisy in Kiev, with more than ten blasts occurring so far. Air defenses are in action. [Sounds of explosions] were heard very well in the city center, they woke us up," eyewitnesses have told TASS.

TASS also learned that explosions were followed by a fire, seen in Kiev's Dneprovsky district on the left bank of the Dnepr River.

Ukraine’s official air raid alert portal earlier said that a warning had been issued for the capital and a number of other regions.