NEW: Russia has begun firing into the besieged city of Mariupol from 7 ships in the Sea of Azov: senior U.S. defense official

This is a new development from yesterday, the official said. At least some 🇷🇺 troops have broken into Mariupol, which has been encircled for over 3 wks.

— Jack Detsch (@JackDetsch) March 22, 2022