A pig farm owner in Pocheon, Gyeonggi Province, has been arrested on the suspicion of disposing of the dead body of a Thai farm worker earlier this month, according to local police Wednesday.

According to the Pocheon Police Station, the farm owner is alleged to have buried the body of the 60-something Thai man on a nearby hill on March 2 at around 8:00 a.m. The deceased had lived and worked at the farm for nearly a decade and a post-mortem autopsy suggests he likely died of underlying health problems, rather than as a result of homicide.

Police recovered the body the same day, after receiving a missing person report from a neighbor. The investigators are said to have secured surveillance camera footage showing the farm owner moving his tractor in the direction of the hill.

The detained suspect has admitted to the charge.

Civic group Pocheon Migrant Workers Center raised suspicions that the deceased worker, who was an illegal migrant, may have been subjected to inhumane working conditions. It is reported that he, along with the farm’s owner, raised almost 1,000 pigs at the farm.

A small room adjacent to the pen where the deceased man worked had no heating and black mold on walls and ceilings, according to Kim Dal-sung, head of the PMWC.

“When I entered the room, it was hard to breathe because of the smell of pig excrement. Given that the deceased worked there for more than a decade, the potential link between his death and the poor working conditions should be thoroughly investigated,” Kim said.

The police, the labor ministry and other related organizations are currently examining the farm’s work environment, while looking to determine whether the worker had been subjected to mistreatment.