https://en.wikipedia.org/wiki/Outer_Space_Treaty says they inherited the USSR’s entry into the “Treaty on Principles Governing the Activities of States in the Exploration and Use of Outer Space, including the Moon and Other Celestial Bodies”, which, among others, states states shall be liable for damage caused by their space objects, so they should fess up.

Depending on where it falls, in today’s political climate, they might say it’s part of a special military operation against nazis, though.