Kapook.com news site reported investigators said DNA tests confirmed that nine infants found in a Thai condominium last week shared a common father. Each child was under the care of individual nannies.
The apartment and the nannies were registered under the name of the Japanese man, who had since fled the country, police said.
Officials placed the infants in the care of social services.
Thailand has re-examined its surrogacy laws following a scandal involving Gammy, a surrogate baby with Down syndrome, left behind in Thailand by an Australian couple.
Authorities have been examining surrogacy clinics and practices around the country, but complain that legal loopholes make cases difficult to investigate.
- AAP