Latest "Kerch strait" stories
Among those Russia returned was Ukrainian film director Oleg Sentsov, whose conviction for preparing terrorist attacks was strongly denounced abroad, and 24 Ukrainian sailors taken with a ship Russian forces seized last year.
Ukraine is demanding the immediate release of its sailors and ships from Russian custody, arguing that failure to do so would breach the country's rights.
Personnel on the dock landing ship Fort McHenry have treated 25 sailors and Marines for a viral infection similar to mumps.
By Mark D. Faram