Mariupol Officials: Second Mass Grave Found

A makeshift cemetery has been discovered near the city of Mary, with claims of it being a mass grave site. Although unverified, this is the second such site reported this week. Ukrainian officials accuse Russian forces of burying up to 9,000 civilians to hide atrocities.

What is the significance of the second reported mass grave site discovered?

How many civilians are reported to have been buried to conceal atrocities?