Premchai, president of Italian-Thai Development Plc, was arrested, along with three other people, at a no-camping zone in the Thungyai Naresuan wildlife sanctuary in Kanchanaburi for poaching on Feb 4.
Gen Srivara complained that several groups had tried to discredit him on social media regarding the probe.
If there is sufficient evidence to prove the groups were colluding against him to destroy his reputation, he will pursue a lawsuit against them, he said.
Netizens have launched a campaign criticising the deputy national police chief using the hashtag #NoSrivara.
Gen Srivara said the police investigation will be complete today (Mar 8). Police would decide whether to press additional charges including bribery against the suspects.
After a month since the illegal hunting of animals in the wildlife sanctuary, the public and NGOs have been pressuring the police investigation team for results.
They fear the evidence collected might be weak and eventually not be able to bring the suspected culprits, including Premchai, to court.
They have vowed to closely monitor the case and launched various campaigns to raise public awareness about the case, including wearing black leopard masks and spraying graffiti.
In the campaigns, the black Indochinese leopard found dead in the camp site where Premchai and other suspects were arrested on Feb 4, has become a symbol of the desire for the tycoon to be prosecuted.
Also yesterday, Pinsak Suraswadi, deputy chief of the Department of National Parks, Wildlife and Plant Conservation, said forensic and DNA tests indicated some of the DNA found in meat in a soup cooked by Premchai's group in the national park before they were arrested belonged to the Indochinese leopard, while other meats present were silver pheasant and boar.
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