A Thai lawyer has said a Japanese millionaire is the father of the babies, who were born to Thai surrogate mothers.

Military Police and welfare workers who raided the condominium also found nine Thai and Japanese child-minders and a woman who was about four months pregnant, Thai media reported. The woman claimed to be a surrogate mother.

The babies have been taken to an orphanage in Nonthaburi Province, outside the capital. Authorities plan to do DNA tests on the babies.

Thai lawyer Ratprathan Tulathorn, who told authorities he was acting for the Japanese man, said the man wanted the babies to take back to Japan to run his business when they grow up.

''The Japanese father loves his babies and comes to visit them every week,'' Mr Ratprathan said, adding the man plans to try to sue to get them back.

Thairath TV journalists working undercover discovered the condominium in the Lat Phrao area in central Bangkok only days after Fairfax Media revealed the plight of Gammy, a six-month-old baby with Down syndrome who was left with his Thai surrogate mother by his Australian biological parents. The case caused a furore in Thailand and Australia, and prompted Thai authorities to intensify a crackdown on the booming Thailand surrogacy industry.

Thairath reporters were told by people living near the condominium that ''it is very noisy. We heard babies cry. It has been over a year, but we still hear babies cry.''

The reporters said two of the babies were taken to hospital last week suffering fevers. They said four of the babies were found sleeping on beds in one room and the others were in different rooms.

A woman at the condominium said nannies were paid to care for the babies. A Japanese woman questioned said she was expecting to accompany the babies to Japan.