Ukraine's air defense units shot down four Russian aircraft, two helicopters on March 16

That's according to Vadym Denysenko, an adviser to the Ukrainian interior minister, Ukrinform reports.

"Our air defense forces shot down a missile in Kyiv this morning. And in general, we must thank our air defense forces for what they are doing in Kyiv, and for shooting down at least four enemy aircraft yesterday. We shot down two helicopters and continue to hold our positions, not allowing the Russians to advance anywhere in principle," Denysenko said.

Currently, according to him, the main sore point remains Mariupol.

"It's our pain, and it's our biggest problem to date. Mariupol is standing, Mariupol is under the Ukrainian flag, and Mariupol continues to defend itself," Denysenko said.