After a series of unsuccessful raids at the home of former Chartthaipattana Party MP Chada Thaised, the Central Investigation Bureau (CIB) shifted strategy to target his convoy of cars in Uthai Thani, allegedly finding pistols and narcotics.
Mr Chada is a former local influential politician who entered the national political arena. According to CIB chief Thitirat Nongharnpitak, Mr Chada is believed to have has committed wrongdoing in the lower North and is expanding his influence to other regions.
Police have raided Mr Chada's house numerous times over the years in high-profile operations. But most, if not all, of these raids have ended up without any charges pressed against him. That has raised the question of whether he is effectively above the law.
Six people in the convoy of eight vehicles, including Mr Chada, were apprehended while leaving a funeral ceremony at Wat Lum Khao in tambon Lum Khao of Nong Khayang district.
Police also said they have information the duo are actively involved in bidding price collusion in construction projects in the lower North. Mr Chada seemed aware his house would be raided on several occasions.
It is believed some rogue police officials leaked information about the raids, which gave him plenty of time to remove any illegal items.
Pol Lt Gen Thitirat, therefore, turned his focus to the convoy of cars that accompany Mr Chada. There are normally about 10 cars in the convoy and, as expected, police say they found and seized weapons and drugs from Mr Chada's convoy on May 27.
"Travelling together in such a [huge] group of cars and carrying guns is a bad example for young people," Pol Lt Gen Thitirat told the Bangkok Post.
"Of course, this arrest [on May 27] was just the beginning. He should stop being such an influential thug," he said, adding the police who took part in the May 27 operation are all top-notch ones.
The reason the authorities focused on Mr Chada's convoy instead of his house was because intelligence information showed there were might be weapons hidden in the cars, he said.
He also cautioned other influential figures that similar search techniques will be applied in future crackdowns on them if they continue to act as if they are above the law. "Why target Mr Chada? The Crime Suppression Division [CSD] has learned over the years that this suspect continues to be actively involved in illegal activities including bidding price collusion in Nakhon Sawan and Kamphaeng Phet," he said.
"Many of his [Mr Chada's] men have been extorting money from victims and we have found his gang members involved in some murder cases," he added.
Suphareuk Eiam-laor, Mr Chada's lawyer, said no guns or illegal items were found in a search of his client, but those who were accompanying him were carrying firearms. All of them are facing charges of conspiracy to carry firearms in public places without a permit, he said.
Mr Chada was arrested on charges of masterminding the murder of Somkiat Chanhiran, a secretary to Prasaeng Mongkolsiri, a former Thai Rai Thai MP, in 2003. He was acquitted later in 2005, said Pol Lt Gen Thitirat.
Mr Chada had also been accused of being involved in the murder of Pol Col Krerkrit Niyomserm, a former chief of Sai Ngam police station in Kamphaeng Phet who was gunned down outside his home in Nakhon Sawan on April 18, 2011. Mr Chada denied any involvement in the murder.
Pol Lt Gen Thitirat is one of the police cracking down on criminal activities in which Mr Chada is suspected to be involved. The police officer began dealing with Mr Chada when he became CSD chief. His inquiries led to a series of raids at the suspect's house in Uthai Thani starting in 2014.
The counter-corruption division of the CIB is also pursuing charges against Mr Chada in connection with his alleged involvement in bidding price collusion in state projects, said Pol Lt Gen Thitirat, declining to add details.