Police in Guinea-Bissau raided the offices of Danish researchers on Monday, seizing doses of hepatitis B vaccine intended for a vaccine trial for newborns. International health experts have called the trial “unethical,” but anti-vaccine Health Secretary Robert F. Kennedy Jr. has attempted to fund it with US taxpayer dollars.

Under Kennedy, the US Centers for Disease Control and Prevention announced in December that it had awarded the Danish researchers—led by married couple Peter Aaby and Christine Stabell Benn of Bandim Health Project—an unsolicited $1.6 million grant to run the trial. Aaby and Stabell Benn are controversial vaccine researchers who claim vaccines cause overlooked harms. They have been repeatedly praised by Kennedy, but are currently under investigation for alleged scientific misconduct by Danish authorities.

Plans for the trial were halted in January as widespread condemnation erupted over the trial’s design, which would potentially expose thousands of newborns in the country to hepatitis B, risking a lifelong infection that can lead to liver cirrhosis, cancer, and premature death. Outrage flared again after a Rolling Stone story earlier this month claimed the CDC set aside another $1.6 million in funding in late September and planned to move forward with the trial.

For now, the trial is not moving forward; Guinea-Bissau officials have not signed off on the trial. In a press conference last week, the country’s health minister, Quinhin Nantote, confirmed that the government had not yet authorized it.

“Any scientific research initiative involving human beings, particularly children, ‌must ⁠strictly comply with applicable national legislation, international ethical principles, competent evaluation and approval mechanisms,” Nantote said, according to Reuters.

In response to media reports that the trial will move forward, Nantote told the Guardian, “This is not even remotely true.”

Now it appears that officials in Guinea-Bissau have opened an investigation into Aaby and Stabell Benn’s work. In a Facebook post Monday, translated from Portuguese, the judicial police announced they carried out a “search operation at the facilities of the Bandim Health Project in Bissau, which culminated in the seizure of a batch of hepatitis B vaccines intended for vaccination of children in the country.”

The police added that the operation “aimed at clarifying the circumstances related to the said batch of vaccines.” The announcement noted that “the seizure constitutes an investigative procedure and does not allow, in itself, to conclude the existence of irregularities in the quality, safety, or effectiveness of the vaccines.”