Police in South Korea arrested a man under suspicion of involvement in the murder of a Korean tourist in Pattaya, Thailand, according to the Gyeongnam Provincial Police Agency on Monday.

According to police officials, a Korean man in his 20s was apprehended at his home in Jeongeup, North Jeolla Province, on Sunday evening and placed under emergency arrest for allegedly murdering a man and abandoning his body.

The police had been tracking the suspect’s whereabouts after learning that he had entered South Korea from Thailand on May 9.

Besides the suspect now in custody, police believe that there are two other suspects behind the kidnap and murder of the 34-year-old Korean in Pattaya. The two suspects, who were also identified as Korean nationals, are still being tracked.

On Saturday, Thai police officials discovered the victim’s body inside a black plastic container filled with cement in a reservoir in Pattaya.

The victim, identified by his last name Roh, had entered Thailand for travel purposes on April 30 and reportedly went missing on May 7, according to the Korean Embassy in Thailand and local media outlets. Police officials began a search for Roh after his mother reported to the Korean Embassy in Thailand that she had received a phone call on May 7 from an unknown man who claimed that her son would be killed if a ransom of 3 million Thai baht ($81,500) was not paid.

The person on the phone reportedly told the mother that Roh had caused them great damage by “throwing away drugs,” and threatened to dismember Roh and sell his organs on the black market if the money was not paid by May 8.

After receiving the mother’s report, the Korean Embassy in Thailand requested cooperation from the Thai police.

Police then searched security camera footage and found that Roh was escorted by two men into a rented car heading toward Pattaya at around 2 a.m. on May 3. They then changed their vehicle to another pickup truck and on the evening of May 4, the pickup truck was allegedly seen driving to a nearby store to buy a black plastic barrel and rope.

Thai police later traced the pickup truck to a location near the Mabprachan reservoir and eventually discovered what they suspected to be Roh’s body in the plastic barrel with cement. Thai authorities are conducting an autopsy to determine the exact cause of Roh’s death.

“Further details behind the case cannot be disclosed as it is currently under investigation,” police officials said on Monday.