US prosecutors move to drop frog embryo smuggling charges against Russian-born Harvard scientist who claimed vindictive prosecution

Kseniia Petrova, a Russian-born biomedical researcher at Harvard Medical School, won her case after federal prosecutors in Boston filed to dismiss the charges on Tuesday, citing the disproportionate resources the case would now require. A judge had ruled in her favour on the question of evidence-gathering, allowing her to pursue her claim that the Trump administration had targeted her for prosecution — a claim prosecutors labelled "meritless" but ultimately declined to fight.

Petrova was detained at Boston airport in February 2025 after customs agents found undeclared frog embryos in her luggage.

She insisted her supervisor had asked her to bring back the samples from France for research experiments, and she pleaded not guilty.

Her lawyer William Fick said she had shown 'tremendous courage' and called the dropped charges the end of a 'terrible ordeal'.