Police in Namibia have re-arrested 13 people freed Monday, after being held on charges of high treason. A judge ruled that the men were illegally extradited from Botswana and Zambia to stand trial for a 1999 secessionist uprising in the Caprivi strip.

Judge Elton Hoff ruled late Monday that Namibian authorities had violated extradition laws in bringing the 13 defendants back into the country to stand trial. The judge said his court had no jurisdiction to try them, and he ordered their immediate release.

But their lawyer, Patrick Kauta, says police have re-arrested the 13 people on new charges, unrelated to the ones they were originally facing.

"In any event, whatever they do, the 13 will never be part of the high-treason trial anymore," he said. "So I think it is just a flimsy underhanded police method of trying to keep these people still in custody."

Mr. Kauta praised the judge's decision to free his clients, saying it shows the independence of the Namibian judiciary and its willingness to rein in the police when they overstep their bounds.

In his ruling Monday, Judge Hoff said the Namibian military is working under difficult and dangerous conditions to restore order in the aftermath of the Caprivi attacks. But he said that was no excuse for failing to follow proper extradition procedures.

The Namibian government has indicated that it wants to appeal the decision.

Most of the 13 had previously been granted refugee status in Botswana or Zambia, but they were deported as illegal immigrants rather than being formally extradited. The Namibian government believes several of the freed detainees were masterminds of the attacks.

In August 1999, insurgents attacked Namibian government buildings the northeastern Caprivi strip with rocket-propelled grenades, mortars and assault rifles, killing 16 people.

The 13 prisoners were among about 120 on trial for high treason, murder, conspiracy, and other charges relating to the failed uprising. One of them is John Samboma, the alleged commander of the Caprivi Liberation Army, the group blamed for the deadly attacks in the border town of Katima Mulilo.

Namibia's handling of the Caprivi trial has been controversial from the start. Local and international human rights groups believe many of the detainees have been tortured or mistreated in police custody. Scores of them have filed civil lawsuits against the state.

The trial has also been plagued by a series of long delays, and only resumed late last year. Most of the defendants have been in prison for more than three years. The human rights group Amnesty International says at least 11 defendants have died in custody.

Amnesty International also says a number of the defendants appear to be on trial for sympathizing with the Caprivi secessionist movement, even though they had no direct involvement in the uprising.