Police personnel have been posted in strength in areas where some Jallikattu organisers even threatened to organise the sport defying the ban, police said.
In some places, black flags had been hoisted after the Supreme Court today declined to lift its stay on the Centre's notification allowing the sport, they said.
Five Jallikattu competitors observed a fast in front of the District Collectorate here demanding permission to hold the sport during this Pongal festival.
Police said they were keeping a close watch on the developments and would take severe action if anyone violated the apex court order.