India, Jan. 20 -- Prime Minister Narendra Modi on Tuesday warned about "ghuspaithiyas", or illegal immigrants, and 'urban Naxals', saying the central government will act against groups that "pose a threat to the country's security", and political parties that "offer them security" should be exposed.

"Today, the country faces a very significant challenge from infiltrators. Even powerful countries in the world are acting against infiltrators in their own nations and expelling them," the prime minister said while addressing party workers after Nitin Nabin was elected as the Bharatiya Janata Party's (BJP) new national president.

In an indication of the government's tough stance against the aforementioned set of people, the PM said no nation...