Who is an extremist leader?

Notable Extremist Leaders

Lala Lajpat Rai, Bal Gangadhar Tilak, and Bipin Chandra Pal are the prominent figures behind the extremist movement, commonly referred to as Lal-Bal-Pal, representing Punjab, Bombay, and Bengal respectively. Additionally, other influential leaders include Aurobindo Ghosh, Rajnarayan Bose, A. K. Dutt, and V. O. C. Pillai.

Source: NCERT Notes Indian National Movement Extremist Period - BYJU.