PETALING JAYA: The prosecution's key witness in the RM42 million SRC International case against former prime minister Datuk Seri Najib Abdul Razak was brought back to the country recently, after three months on the run in Thailand.

The man, who runs a currency exchange business, was tracked down in Bangkok by a Malaysian Anti-Corruption Commission (MACC) task force which had been looking for him since May. With assistance from Thai police, the MACC team persuaded him to return to Malaysia.

Upon his arrival here last week, he was detained by MACC and placed under a week-long remand.

It is learnt that the businessman has since pledged to cooperate with investigators and has agreed to be the prosecution's key witness.

The businessman is suspected of having aided in many transfers of the multi-billion ringgit in funds linked to 1Malaysia Development Berhad (1MDB) and its former subsidiary SRC International Sdn Bhd.

Sources said the businessman, who is in his 50s, fled Malaysia and went into hiding in Thailand soon after a probe on the financial scandals commenced on the orders of the new government in mid-May.

It is believed that the man has vast information on the illegal movement of the funds both into and out of the country as his services were engaged by the perpetrators, including the No. 1 person-of-interest, financier Low Taek Jho, also known as Jho Low.

The whereabouts of Low remains uncertain but investigators believe he is hiding either in China, Taiwan or Hong Kong.

While MACC has concluded the RM42 million SRC International scandal, that saw Najib facing multiple charges, the RM2.6 billion 1MDB investigations are ongoing and said to be about 60% completed.

Although investigators are faced with hurdles such as the difficulty in recording the statements of a number of people who have either fled the country or are uncooperative, they believe they can wrap up the probe within the next three months.

Najib pleaded not guilty to three counts of criminal breach of trust and one charge under the MACC Act, involving over RM42 million linked to the SRC International case on July 4.