LONDON (AP) — A U.K. woman who as a teenager ran away to join the Islamic State group lost a legal challenge Friday aimed at restoring her citizenship, which was revoked on national security grounds.

Shamima Begum, one of three east London schoolgirls who traveled to Syria in 2015, resurfaced at a refugee camp in Syria last year and told reporters she wanted to come home. But her apparent lack of remorse has triggered criticism in Britain and the family has expressed its own shock at her lack of repentance.

Former Home Secretary Sajid Javid revoked her citizenship, but she challenged the decision before the Special Immigration Appeals Commission. She argued she is not the citizen of another country and that Javid’s decision left her stateless.

But the tribunal ruled in Javid’s favor on Friday. Judge Doron Blum said the decision did not breach the Home Office’s “extraterritorial human rights policy by exposing Ms Begum to a real risk of death or inhuman or degrading treatment.”

The tribunal ruled that she was “a citizen of Bangladesh by descent,” and therefore not rendered stateless.

Her attorney, Daniel Furner, said the decision was baffling and would be appealed.

Begum’s family has long argued that she has never had a Bangladeshi passport and that she was from the U.K.

Begum, now 20, was one of three schoolgirls from Bethnal Green Academy who left their homes and families to join IS after boarding a flight from Gatwick Airport to Istanbul. Begum claims she married Dutch convert Yago Riedijk 10 days after arriving in IS territory, with all three of her school friends also reportedly marrying foreign IS fighters.

She gave birth to three children while in Syria, all of whom died.

Although it’s unclear whether Begum has committed a crime, her case has thrown into sharp relief larger questions about how Western societies will deal with others who joined IS, but want to return to their home countries now that the extremist group has collapsed.