BANGKOK, Thailand -- The military junta, which overthrew prime minister Thaksin Shinawatra in a coup, cancelled his diplomatic passport on Wednesday (January 10) after linking his supporters to deadly New Year bomb blasts.

The military-installed government on Wednesday (January 10) also interrogated Mr. Thaksin's multi-millionaire son, Panthongtae, for alleged corruption in a telecommunications deal, which the prime minister and his family made with Singapore's government one year ago.

"Taking into consideration the appropriateness, and security concerns, the diplomatic passports of Thaksin and wife have been revoked," Foreign Ministry deputy spokesman Kiatthikhun Chartprasert told reporters on Wednesday (January 10).

A rightwing, royalist faction of Thailand's U.S.-trained military moved tanks, armored personnel carriers and Humvees on Sept. 19 to stage a bloodless coup while Mr. Thaksin was in New York preparing to speak at the United Nations.

After the coup, Mr. Thaksin used his diplomatic passport to travel to London, Hong Kong, Indonesia and China.

Just before the announcement about his cancelled passport, Mr. Thaksin's lawyer said the toppled leader was in Beijing.

Mr. Thaksin and his wife Pojaman may be able to travel on ordinary passports, but it was not immediately clear if the couple possessed those documents. Mr. Thaksin's wife was recently in Bangkok.

The military junta yanked their diplomatic passports after blaming Mr. Thaksin's supporters -- which it denounces subversive "undercurrents" -- for destabilizing this Southeast Asian country.

During Bangkok's New Year celebrations, eight small time-bombs killed three people and injured 38, including nine foreigners.

The coup leaders dismissed speculation that Islamist guerrillas active in the south had extended their bloody separatist fight to Bangkok.

"From the available evidence, the blasts were masterminded by vested interests losing out in the political struggle," Defense Minister Boonrawd Somtas told reporters on Monday (January 8), echoing similar conclusions voiced by other coup leaders.

Outraged by the New Year bomb blasts, many Thais criticized the junta for not providing security, despite naming itself a "Council for National Security".

Thai politicians, columnists, activists and others also complained the junta was "too nice" to Mr. Thaksin and his family, amid widespread demands that the junta should have immediately seized their assets, charged them with corruption, and revoked their passports.

The coup leaders have clamped Thailand under martial law, banned political activity, ripped up the constitution, and invoked media censorship.

An editorial cartoon in the pro-coup Nation newspaper on Wednesday (January 10), showed a coup leader undergoing an "emergency brain transplant" in which his "peace and reconciliation" brain is scooped out, to be replaced with a "not nice guy action" brain.

Mr. Thaksin chose self-exile after being overthrown, but was later warned by the junta not to return home because his appearance could spark unrest.

Mr. Thaksin is widely despised in Bangkok among the middle and upper classes, but was popular with urban and rural poor people who benefited from his populist policies, easy loans, inexpensive health care and other schemes.

The "smooth as silk" September coup was cheered in Bangkok amid shrill claims by officials and the media that the military should help write a new constitution and stop corruption within the civilian government.

But the mood soured after the junta failed during its first few months to bring charges against Mr. Thaksin and his cronies.

Amid several corruption investigations, Mr. Thaksin and his family are accused of not paying capital gains tax when they sold their shares in Shin Corp., a telecommunications conglomerate they founded.

The January 2006 sale to the Singapore government's Temasek Holdings netted an estimated 1.8 billion U.S. dollars for Mr. Thaksin and his family.

Mr. Thaksin's adult son, Panthongtae Shinawatra, spent at least two hours on Wednesday (January 10) answering questions about his role in the sale.

Mr. Panthongtae reportedly told an Assets Examination Subcommittee that his mother's personal secretary conducted the sale, on behalf of Shin Corp., to the Singaporeans.

"Wiroj Laohapan, a subcommittee member, quoted Panthongtae as testifying that he did not know much about the sale of the shares of Shin Corp., and his duty was just to sign the appropriate documents while Kanjanapa Honghern, personal secretary of his mother, [Mrs.] Pojaman, was in charge of all procedures involving the controversial sale," the Nation reported on Wednesday (January 10).

"According to Wiroj, most of his [Panthongtae's] answers to the subcommittee's questions were: 'No, I don't know'," the report said.

The personal secretary was scheduled to testify on Jan. 12. Mr. Thaksin's adult daughter, Pinthongta, was due to be questioned on Jan. 24.

Everyone who made money in the sale has insisted it was legal, and claimed Thai laws allow a tax loophole on such deals.

Their testimony was for possible use in preparing formal corruption charges, and was not a trial.

"We are in the process of collecting information and evidence concerning the allegations," Klanarong Chantik, an Assets Examination Subcommittee member, told reporters.

"Everything is fine," said Sak Korsaengrueng, another Assets Examination Subcommittee member.

"He [Panthongtae] could answer nearly all questions, which were basic in nature. It is likely that we will not invite him again for testimony, unless we need more information," Mr. Sak told reporters.

Copyright by Richard S. Ehrlich, who has reported news from Asia for the past 28 years, and is co-author of the non-fiction book of investigative journalism, "HELLO MY BIG BIG HONEY!" Love Letters to Bangkok Bar Girls and Their Revealing Interviews. His web page is http://www.geocities.com/asia_correspondent