Kseniia Petrova was detained for four months after arrest with research samples, and feared deportation to Russia

Federal prosecutors have dropped all criminal charges against a Russian scientist who spent four months in immigration detention after flying into Boston with frog embryos intended for cancer research at Harvard Medical School.

Kseniia Petrova, 31, was arrested in March 2025 after returning from a vacation in France, where she had visited a laboratory specializing in cutting extremely thin sections of frog embryos. During her visit, she obtained a package of samples for her research back in the US.

Girl suffered alleged abuse at foster home immigration officials placed her at after separating her from mother

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For five months, the young father waited for his three-year-old daughter’s release from federal custody after she crossed the US-Mexico border with her mother, hoping through delays for their safe reunion.

Only when he turned to the courts as a last resort did he learn that the girl had suffered alleged sexual abuse at the foster home where she’d been placed after immigration officials separated her from her mother.