25 detained in Thailand terror investigation

BANGKOK, Thailand (CNN) -- Thai police detained for questioning 25 people from other countries as part of a joint operation with the United States in the fight against terrorism, sources told CNN Friday.

Thai authorities watched the group of 25 -- including 10 Pakistanis -- for several months, the sources said, intercepting their telephone calls and investigating financial transactions before taking them in.

Some were taken into custody for their alleged involvement in a passport forgery ring but have not been formally charged. Part of the joint investigation centers on the forgery ring.

The U.S. Embassy in Bangkok declined to comment on the report.

Thailand's national police chief said the operation has no connection with Osama bin Laden and his al Qaeda terrorist network, while sources tell CNN it's a wide-ranging investigation that may or may not include links to al Qaeda.

The operation involves the American CIA and FBI and Thai police and military units, including the nation's elite special branch, sources said.

The operation started shortly after the September 11 attacks in New York and Washington and has intensified over the last three months as authorities gathered more information.

Thailand's Prime Minister Thaksin Shinawatra has said he does not believe his country is used as a base for terrorism, but he has agreed to cooperate with U.S. authorities.

It is widely believed that Thailand is a stopover point for criminal elements from areas such as the Middle East and Pakistan, because it is easy to enter the country through Bangkok.