Police are trying to identify more suspects in the 1.57-billion-baht embezzlement scandal at King Mongkut's Institute of Technology Ladkrabang (KMITL) as they continue to track four suspects still on the loose.
Police have arrested four out of eight people issued with arrest warrants.
After inspecting the money trail, police investigators now believe there must be more people involved, said Pol Col Nasa Sawetlek, deputy chief of the Crime Suppression Division (CSD), who is head of the police team probing the KMITL case.
Police investigators are checking to see whether there are any more suspects and to determine who should face an arrest warrant next, the CSD deputy chief said.
Officers have arrested Amporn Noisamrit, head of the KMITL's financial division; Songklod Sriprasong, former manager of Bank of Ayudhya's Big C Srinakarin branch; Poonsak Boonsawat; and Jariwat Sahapornudomkarn.
Somphong Sahapornudomkarn, Kittisak Muttujad, Sombat Sopradit and Chanchira Sopradit remain at large.
They are wanted on charges of document forgery, theft, and money laundering, Pol Col Nasa said.
As for actress Sawika "Pinky" Chaiyadech, whose name reportedly appears as a business partner of Mr Kittisak, Pol Col Nasa said it is not necessary to summon her for questioning for the time being because investigators have yet to expand their probe to cover the suspect's business partners.
A source close to Sawika said the actress' mother, Sarinya Chaiyadech, was shocked to learn from the media that her daughter, who is now in Japan on her honeymoon, has about 30% of the shares in Acting One Entertainment Co, which is one of seven companies owned by Mr Kittisak.
Ms Sarinya said the media reports about her daughter's shares in the company were not true, the same source said.
However, Ms Sarinya conceded that Sawika does hold shares in KPP Production Co, another company belonging to Mr Kittisak, but she has never been involved with running the company.
Her name was used by company shareholders after she was persuaded by a man identified as "Kuek" to join the business to help produce a TV series three years ago. But there had not been any progress in the production of the series, according to Ms Sarinya.
Meanwhile, the investigation team have revealed what they discovered during a search of a house owned by Mr Kittisak's mother, who police believe has already fled to Hong Kong, Pol Col Nasa said.
The team is verifying whether a vast amount of money and a large number of land title deeds reportedly found during the house search are actually connected to the scandal, he said.
Pol Col Jiraphop Phuridech, acting chief of the CSD's Sub-division 1, revealed that a total of 29 land title deeds are currently held by Radom Muttujad, Mr Kittisak's mother.
Mr Kittisak is believed to be a key suspect in the case because he was the person who had the other suspects transfer the embezzled money to their accounts before transferring the money again from those accounts to his own ones, Pol Col Nasa said.
Mr Kittisak also allegedly paid kickbacks to the other suspects for their help, Pol Col Nasa said.
Police have also discovered that Muttujad Co, also operated by Mr Kittisak, runs various types of businesses including real estate, modelling, entertainment and TV production, and legal consultancy.
Police are looking into the company's money trail before it was a registered company in 2012.
The investigators and the KMITL worked out that a total of 1.57 billion baht went missing from the institution's accounts between 2012 and last month, he said.
Actor Pakorn Chatborirak yesterday sought a meeting with investigators over his purchase of a 13.5-million-baht Lamborghini from Mr Kittisak, Pol Col Nasa said.
Pakorn showed the officers some documents about the car deal and insisted he has nothing to do with the KMITL case, the officer said.
On Monday, police will question the KMITL's current financial officials and their predecessors regarding their approvals of transactions involving the missing money, Pol Col Nasa said.