The U.S. military should immediately either charge or release a CTV journalist who has been held prisoner at a base in Afghanistan for three months, a pair of advocacy groups say.

Jawed Ahmad, also known as Jojo Yazemi, was detained in late October in the southern city of Kandahar, probably over allegations he had contact information for Taliban leaders and possessed a video of Taliban materials, his brother Siddique Ahmad said.

"We are deeply troubled that Jawed Ahmad has been secluded in a U.S. military base for nearly three months without charge," Joel Simon, executive director of the New York-based Committee to Protect Journalists, said in a statement.

"The United States military must explain the reason for his detention and accord him due process. If he is not charged with any crime then he must be released immediately."

The 22-year-old Ahmad had worked in journalism, including gigs for CTV, for about a year, according to New York Times correspondent Carlotta Gall, who knows him and his brother from her reporting trips to Kandahar.

"All of the local press corps have numbers of the Taliban and interview them regularly," she said. "Jawed had nothing more than the others in the way of contacts with the Taliban."

The international press-freedom organization Reporters Without Borders called Ahmad's imprisonment "unjustified."

"We call on U.S. Defence Secretary Robert M. Gates to intercede on behalf of this young Afghan reporter, who is clearly the victim of an arbitrary decision," the organization said in a statement issued Tuesday.

"We point out that it is not illegal for journalists to have professional contacts with all parties to a conflict including, in Afghanistan, the Taliban."

Maj. Chris Belcher, a U.S. military spokesman, acknowledged Tuesday that Ahmad is being held at Bagram Air Force Base north of Kabul, but he said he could not discuss details of the case.

Human rights groups have denounced the Bagram base as the equivalent in Afghanistan of U.S. prisons at Guantanamo Bay, Cuba, and Abu Ghraib, Iraq, both of which have been marred by cases of prisoner torture.

Siddique Ahmad said that in January, with the Red Cross's help, he was able to videoconference with his brother, who reported being beaten during his imprisonment.

Mysterious arrest

Ahmad also told the Committee to Protect Journalists that his brother was arrested when he went to Kandahar airport for what he thought was a meeting with his CTV colleagues.

But it's unclear who called him. CTV correspondent Paul Workman was in Kandahar at the time but had not planned on meeting with Jawed Ahmad that day, the Canadian network said.

"Since his disappearance in late October, CTV News has been deeply concerned about Jojo Yazemi's whereabouts and well-being," Robert Hurst, president of CTV News, said in an e-mail.

"CTV News has made inquires to NATO, Canadian, and U.S. military officials. No information has been forthcoming. CTV News has also made representations to the International Committee of the Red Cross and diplomatic channels including the Canadian Embassy in Kabul, Afghanistan."

Two other journalists are currently being held by U.S. forces, according to Reporters Without Borders: Sami Al-Haj, an Al-Jazeera cameraman imprisoned at Guantanamo Bay, and Pulitzer Prize-winning Associated Press photographer Bilal Hussein, detained in Iraq.

With files from the Canadian Press