With the political furore boiling over the EC's handling of the election, Vasana's trip was seen as way to avoid the heat - and visit his son, who is studying there.

But, interestingly, he appeared to have a travelling companion, or two. Vasana sat in first-class seat 2A, while sitting next to him in 2B, was Sawang Munkhongcharoen, the politically connected businesswoman.

Sawang recently came out "clean" after a case filed against her by the Securities and Exchange Commission over a dubious financial deal involving the real-estate assets of Natural Park. Several years ago, she was known to be on close terms with the Shinawatra family.

Occupying a seat behind Vasana and Sawang in the first-class section was Ms Phaithoon Phongkesorn, deputy director-general of the Revenue Department.

Phaithoon signed a letter of confirmation in November last year to assure Panthongtae and Pinthongta Shinawatra, the caretaker prime minister's two eldest children, would not be subject to any tax on their share transactions through Ample Rich, a nominee company incorporated in the British Virgins Island.

Later, the Shinawatra clan sold Shin Corp to Temasek of Singapore for more than Bt70 billion without having to pay any taxes.

Phaithoon also confirmed in December last year that the Revenue Department did not apply double standards in its failure to collect tax from Khunying Pojamarn Shinawatra, who had transferred stocks to Banaphot Damaphong, her brother.

Another "no tax" case involved Thaksin Shinawatra's transfer of stocks to his sister, Yingluck. Phaithoon said both cases did not require the payment of tax.