In a habeas corpus petition filed on Tuesday, the ACLU accused U.S. immigration authorities of unlawfully detaining the pair and violating longstanding federal protections.

A 38-year-old pregnant woman from Ghana, identified as Anabella Gyasi, and her four-year-old son have reportedly been detained for more than one week at Washington Dulles International Airport in the United States, over President Donald Trump administration’s immigration enforcement policies.

The American Civil Liberties Union (ACLU) disclosed that Gyasi and her son have remained in the custody of U.S. Customs and Border Protection (CBP) since May 19 after arriving in the United States on valid tourist visas.

ABC news reports that, according to court filings submitted by the ACLU, Gyasi had travelled to the United States to secure medical treatment for her son, who reportedly suffers from physical abnormalities affecting both of his hands.

The rights group said the Ghanaian mother and child are being confined inside a locked airport holding room under harsh conditions despite existing regulations that require the release of vulnerable persons, including pregnant women and children.