US prosecutors have dropped all criminal charges against a Russian scientist who was tossed into an immigration jail last year after she landed at a Boston airport with frog embryos intended for her cancer research at Harvard Medical School.
Kseniia Petrova, 31, spent four months in detention following her arrest in early 2025 as she returned from a vacation in France, where she had stopped at a lab specializing in splicing superfine sections of frog embryos and obtained a package of samples for research.
