While three were detained by villagers at Mannakudi after they were found moving around suspiciously, the fourth, a woman, was beaten up by locals at another village after she gave contradictory replies and tried to escape, police said.
The ambulance carrying her to hospital was also detained for some time by the villagers, who demanded that the culprits be nabbed and action against them.
Police said their counterparts in Kerala were also on the lookout for the culprits, as similar stickers had been found pasted on homes on that side of the border.
They said patrolling had been increased following complaints from the villagers.
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Suprintendent of Police Sri Nath said a special team has been formed to nab the gang.
He urged people not to panic and inform police if they saw stickers in an area.