Thai police display pictures of surrogate babies born to a Japanese man who is at the center of a surrogacy. Pic: AP.

BANGKOK (AP) — Interpol says it has launched a multinational investigation into what Thailand calls the “Baby Factory” case: a 24-year-old Japanese businessman who has 16 surrogate babies.

Thai police raided a Bangkok condominium this month and found nine babies and nine nannies. They have since identified Mitsutoki Shigeta as the father of those babies — and seven others.

(MORE: Japanese man in Thai surrogate scandal wanted up to 1,000 babies – report)

Thailand’s Interpol director, police Maj. Gen. Apichart Suribunya, said Friday that investigators want to know why Shigeta had so many children. He has not been charged with a crime and wants his children back. Twelve are in Thailand and four are in Cambodia.

Apichart says Interpol offices in Japan, Cambodia, Hong Kong and India have been asked to probe Shigeta’s background. Police say he appears to have registered businesses or apartments in those countries.