Two vehicles were involved in transporting ex-premier Yingluck Shinawatra to the border province of Sa Kaeo, national deputy police chief Srivara Ransibrahmanakul said Tuesday.
Citing a police investigation, Pol Gen Srivara said one left the former premier's house in Bung Kum district on Aug 23, two days before the Supreme Court was due to rule on Ms Yingluck's criminal negligence case over her administration's failed rice-pledging scheme.
She is believed to have switched vehicles in Min Buri district about 10pm before the second car drove her to Sa Kaeo on the Cambodian border, he noted.
CCTV footage shows a woman was inside the vehicle but it cannot be confirmed whether this was Ms Yingluck, Pol Gen Srivara said, adding experts are in the process of examining the footage.
Efforts are being made to find out who helped Ms Yingluck escape, he noted.
If they helped arrange her transport inside the country before Aug 25, when a warrant for her arrest was issued, they would not be charged, he said.
But if they helped Ms Yingluck flee Thailand, they would be found guilty of breaching the Immigration Act, he added.
Pol Gen Srivara said he could not confirm whether Ms Yingluck has fled overseas as is widely believed.
Meanwhile, the Defence Ministry denied a visit by Deputy Prime Minister Prawit Wongsuwon to the United Kingdom this week was aimed at seeking cooperation in hunting her down.
Gen Prawit, who is also the defence minister, is leading a team of officers from the armed forces on a four-day visit that kicked off Tuesday, according to defence permanent secretary Chaichan Changmongkol.
The deputy premier will hold talks with his British counterpart about a joint military exercise, codenamed "Panther Gold 2017", he noted. The drill, which will be conducted at Infantry Division 9 in Kanchanaburi, involves joint infantry exercises.
Gen Chaichan said the visit is aimed at boosting ties as well as security and military cooperation.
It was not organised to seek cooperation from Britain to track down the fugitive former premier, who has reportedly sought refuge in the UK, he said.
According to a military source, Panther Gold is the first step of a joint military exercise following in the footsteps of Cobra Gold, the biggest annual multilateral military exercise in Asia-Pacific, led by Thailand and the United States.
Panther Gold is a combat exercise, not a Humanitarian Assistance and Disaster Relief (HADR) operation, the source said.
Foreign Minister Don Pramudwinai said there is nothing to suggest Ms Yingluck has sought refugee status with any country.
National Security Council secretary-general Thawip Netniyom said security officers are still trying to determine the whereabouts of Ms Yingluck. A press briefing will be conducted when new details emerge, he noted.
Responding to reports the ousted former premier slipped out of the country via Sa Kaeo, Gen Thawip said it will take time to comb such a large area to discover her exact route.
Gen Prawit said last week a Mercedes-Benz believed to have been used in her escape was captured on CCTV footage passing a military camp in Sa Kaeo on Aug 23.