Police have detained an American woman for allegedly running an illegal nursery on Koh Phangan in Surat Thani.

A team of immigration, tourist and local police and officials raided a rented house at a coconut plantation in tambon Koh Phangan on Wednesday morning.

Inside, they found found about 20 foreign children, aged 3-5 years, along with desks, chairs, toys, teaching materials and meals for children. Some children were studying and others playing in a room.

Three women tourists were working there as babysitters, one Ukrainian and two Israelis, and four Myanmar women as housekeepers.

During the raid, an American woman later identified as Jennifer Keanne Irwin, 40, showed up and said she was the owner of the nursery. Asked to produce a permit to operate the nursery, she could not, according to police

The three babysitters also had no work permits. The Myanmar women were found to be illegal migrants.

Police initially charged Ms Jennifer with being a foreign national setting up or operating a nursery without permission and failing to notify the type of work and the location of a workplace to the local registrar.

The babysitters were charged with being foreign nationals working with no work permits.