The military trials of terror suspects at Guantanamo Bay were thrown into chaos last night after the collapse of the cases of the only two detainees currently charged with crimes.

A judge ruled that he did not have jurisdiction to try Omar Khadr, a “child soldier” who has been held at the US naval base in Cuba since he was 15, prompting a second judge to echo the ruling in the parallel trial of Salim Ahmed Hamdan, who allegedly chauffeured Osama bin Laden.

Judge Colonel Peter Brownback said that the Pentagon had designated Mr Khadr, a Canadian citizen now aged 20 who faced charges of terrorism and murdering a US soldier, as an “enemy combatant”. But Congress last year set up the courts to deal only with “unlawful enemy combatants”.

After the ruling, the judge hearing Mr Hamdan’s case also dropped all charges — the second big legal victory for Mr Hamdan, whose US Supreme Court challenge last year forced the scrapping of the first Guantanamo tribunal system.

Both men will remain prisoners at Guantanamo while US authorities decide whether they can be retried.

Some legal experts said that the decision suggested that none of the 385 other detainees at Guantanamo Bay, held for more than five years without charge, can be brought to trial before the tribunals.

However, the Pentagon said that the issue was little more than semantics.

Times Recommends

• Mandela’s tribe threatens President Zuma
• The French empire strikes back
• Wife of cheating governor exacts a political revenge