A forensic examination shows that the weapon used to kill a rare black Indochinese leopard in Thungyai Naresuan Wildlife Sanctuary in Kanchanaburi in February belongs to construction tycoon Premchai Karnasuta.
"The evidence shows that the gun that killed the black leopard belongs to Mr Premchai. But I have not said that he killed it. We need to investigate further to find out who pulled the trigger," said Pol Gen Jarumporn Suramanee, a retired police forensic expert who has been invited by the Ministry of Natural Resources and Environment to help in the case.
The Environment Ministry has conducted forensic analysis on guns, ammunition, clothes, cars and camping and hunting paraphernalia collected from the camping site where Mr Premchai, president of Italian-Thai Development, and three other suspects were found with animal carcasses and arrested on Feb 4.
Forensic tests on guns and ammunition indicated the leopard was shot eight times with a short gun. A closer examination revealed the beast was not immediately killed but died slowly, Pol Gen Jarumporn said.
DNA from cigarette butts and guns helped confirm the suspects were present at the hunting scene. The DNA from cooked meat showed that it belonged to a female leopard.
The DNA also showed that Mr Premchai sat in the front of the car, on the left, while a female suspect sat behind him.
Despite the forensic tests not being complete, Pol Gen Jarumporn said he was confident the authorities have enough evidence to bring the culprits to justice.
Environment Minister Surasak Kanjanarat said it was clear the alleged poachers were acting as a team.
"All evidence has increased the solid weight of nine charges against Mr Premchai and the gang. We have tried our best to support the interrogative procedure," Gen Surasak said Wednesday.
According to the 1992 Preserve and Protect Wildlife Act, poachers caught hunting protected wildlife face up to seven years' jail and are liable for a fine of up to 100,000 baht, or both.
Even if only one person pulls the trigger, the criminal code stipulates that other people involved in the crime are considered to be accessories and must face penalties equally.
Also on Wednesday, the disciplinary probe team under the Department of National Parks, Wildlife and Plant Conservation (DNP) concluded that Kanchana Nittaya, director of the Wildlife Conservation Office, and Thungyai Naresuan Wildlife Sanctuary chief, Wichien Chinawong were not guilty of letting Mr Premchai and the other suspects enter the wildlife sanctuary. Despite Mr Premchai not having received a legal permit to enter, the probe team found both officials not guilty in relation to the poaching incident.
Meanwhile, the DNP is set to press charges against Mr Premchai for possessing illegal African ivory, according to DNP chief Thanya Nethithammakul.
Possessing African ivory is illegal under Thai law. DNA collected from ivory tusks confiscated at Premchai's residence showed they came from African elephants, forensic tests revealed on Monday.
In this case, fresh evidence emerged that Mr Premchai's wife, Kanita Wittayanand,falsely declared to the authorities the origin of the four ivory tusks found at Mr Premchai's residence. Ms Kanita registered the four tusks as those of domestic elephants.
As a result, his wife might be charged with possessing protected wildlife parts under the 1992 Preserve and Protect Wildlife Act. The penalty is a maximum four-year jail term, a fine up to 40,000 baht, or both.