They were allegedly involved in threatening embassies of various countries.
In raids in several places in the city, three suspected al-Qaeda operatives were today arrested by the National Investigation Agency, police said.
They were allegedly involved in threatening embassies of various countries in India, they said.
Those arrested were identified as M Khareem, Asif Sultan Mohammed and Abbas Ali. While Khareem was arrested from Usmannagar, Asif Sultan Mohammed was picked up from G R Nagar and Abbas Ali from Ismailpuram, police said.
Explosive materials were also seized from them.
Police said NIA raided several places on specific information that suspected Al-Qaeda activists were operating from South Tamil Nadu in and around Madurai.
"Explosive materials and arms have been seized from them," police said, declining to elaborate.
The trio was allegedly running the al-Qaeda unit in South Tamil Nadu. They were also allegedly involved in the explosions that took place in various courts in the country over a period of time, police added.
NIA were also searching for two other suspected Al-Qaeda operatives, Hakeem and Dawood Sulaiman, they said.
(This story has not been edited by NDTV staff and is auto-generated from a syndicated feed.)