Personnel from the Kilpauk police station on Sunday arrested 12 persons, including five women, for gambling.
Following a tip-off, a special team mounted surveillance on a house in Shastri Nagar.
The team raided the house and found its residents placing bets.
The police arrested Raj alias Arockiaraj, 24, Natraj, 50, Karnan, 39, Babu Reddy, 50, and eight others.
Playing cards and ₹72,780 in cash were seized from them. They were released on bail later.