Swiss brothers suspected of involvement in nuclear smuggling have filed a complaint with the European Court of Human Rights against the government.
A lawyer for Urs and Marco Tinner said Switzerland had disregarded the European Convention on Human Rights by keeping the engineers in custody for the last four years without an arraignment. He described the practice as "worthy of Guantanamo".
The brothers along with their father, Friedrich Tinner, are suspected of helping to supply parts for Libya's nuclear weapons programme through a trafficking ring run by Abdul Qadeer Khan, the founder of Pakistan's nuclear programme.
The Swiss Federal Court in August upheld a ruling ordering the brothers to remain in custody pending the outcome of the investigation. Their father had been released from detention previously.
The pair has argued their alleged involvement could no longer be proven after the government ordered the destruction of documents on the case.
In May the Swiss cabinet confirmed that evidence in a nuclear smuggling case had been shredded as per international guidelines.
The Tinners are known to have worked as undercover agents for the United States intelligence service amid speculation that the Swiss government was asked by Washington to destroy any evidence suggesting cooperation with the CIA.