Dutch judges blocked the extradition Tuesday of a terror suspect to the United States, saying he was tortured in Pakistan after his 2010 arrest and it is unclear whether American authorities had any involvement.

The Hague Court of Appeal ruling was a significant victory for the man identified only as Sabir K. in his attempts to avoid being sent for trial in America, but Dutch authorities can still launch a final appeal to the country's Supreme Court.

"He is very satisfied that the role of the Americans is finally being looked at in a critical light," his lawyer Andre Seebregts said. "He has said from the very beginning that the Americans were involved."

Sabir K., who has Dutch and Pakistani nationality, was arrested in Pakistan in 2010 and expelled to the Netherlands in 2011. U.S. authorities accuse him of working with al-Qaida from 2004 to 2010, and of plotting a suicide attack on an American military base in Afghanistan.

In a statement, the Hague appellate court said that U.S. authorities had issued an arrest warrant for K. three days after his detention in Pakistan.

But it went on to say that circumstances of K.'s arrest and detention "raised questions" among the judges, who cited international human rights groups as saying terror suspects are "almost without exception tortured" if detained in Pakistan.

"If the U.S. asked Pakistan to arrest K., knowing he would be tortured by the secret service, this would be a reason to block the extradition," the court said.

Judges had asked the Dutch government to seek clarification from U.S. authorities about their role in the detention, but Dutch justice and security ministry officials refused, saying they did not see the necessity of the request.

The government's refusal meant "uncertainty remained about the involvement of the U.S. in the torture of K.," the court said as it blocked his extradition.

Dutch Security and Justice Ministry spokeswoman Sentina van der Meer said officials were studying the ruling and had no further comment.

Sabir K. was released from Dutch detention earlier this year.