The National Investigation Agency (NIA) on Monday arrested three suspected Al-Qaeda activists from Tamil Nadu's Madurai, said police.
Police alleged that the three suspects had plans to attack Prime Minister Narendra Modi and 21 other leaders.
The arrested men -- identified as M.
Khareem, Asif Sultan Mohammed and Abbas Ali -- also allegedly issued threats to several embassies in India, police said.
Temple town Madurai is around 420 km from here.