Former premier Dr Mahathir Mohammad said the arrest of former PetroSaudi International Ltd director in Thailand yesterday was highly suspicious, akin to a high level conspiracy.

Mahathir said he didn't see why a tourist to Thailand should be arrested for a crime allegedly done in Saudi Arabia without any extradition request from the kingdom.

"Maybe because he is a terrorist, that's why he was arrested by Thailand. If he was only stealing company secret, he won't have to be arrested.

"This man came to Thailand obviously as a tourist unless Saudi Arabia request Thailand to arrest him, I don't see why Thailand should arrest him," he told reporters after a function in Kuala Lumpur today.

According to international media reports, Swiss national Xavier Andrea Justo was arrested in Koh Samui, a Thai resort island, on Monday for attempting to extort 2.5 million Swiss francs (US$2.7 million) from London-based PetroSaudi International Ltd.

Justo was alleged to have used stolen confidential company information as leverage.

Mahathir dismissed the arrest as the latest attempt to cover up for 1MDB's dealings with PetroSaudi.

Work of clever propagandists

He alluded that the media circus surrounding Justo's arrest may also be an attempt to discredit his criticisms of Putrajaya's handling of the 1MDB controversy.

"I will (have to) see what (the Thai authorities find out). But the circumstances of the arrest are suspicious. It's like there was planning by very intelligent people.

"I dont know, we are finding some very clever propagandists are operating, now my face is blackened already and my legacy destroyed," he said.

Following reports on Justo's arrest, Putrajaya appears to have adopted a narrative which described the Swiss national as a disgruntled PetroSaudi employee who peddled "tampered" company information to whistleblower website Sarawak Report .

This information, including email communication and Blackberry Messenger chat logs, was published by Sarawak Report and were then used by some Malaysia media organisations in their reports which were critical of 1MDB's business decisions.

The basis of this narrative appears to stem from a New Straits Times report, which quoted an anonymous source from London-based cyber-forensics firm Protection Group International (PGI) claiming that they have evidence that the information was indeed tampered with.

Trapped in lies

1MDB itself has also issued a statement claiming that the information published by Sarawak Report had earlier been tampered with.

However, Mahathir dismissed such claims, stressing that any form of clarification coming from 1MDB had always been ambigous.

"It is not clear. It is wrong. Now they are talking about email. Emails cannot be altered once it is sent through the phone. The receiver will (get it as it is).

"You saw (what happened) in the United States. They even tapped the French president's email. Now they claim the emails were altered.

"If we look at the sequence, it was not altered," said Mahathir, who stressed that the narrative that followed Justo's arrest appeared to be a cover-up attempt.

"When we lie, we will be trapped when we try to extend the lie. It will be hard to make it fit with the original lie," he said.