The North-East Division Police detained 32 foreign nationals, including 19 men and 13 women, in a special operation launched on Monday.
North-East Division DCP Anoop A Shetty said the operation is to check the excess stay of foreigners without valid documents. Most of those detained are from African countries whose identities and addresses have not been confirmed.
They are being questioned and legal action will be taken against them, Mr Shetty said.