South Asia expert Stephen Cohen 'dies'.

Lahore -- American political scientist and professor of security studies Stephen Philip Cohen reportedly passed away Sunday morning.

He was a prominent expert on Pakistan, India, and South Asian security, a senior fellow in foreign policy studies at the Brookings Institution and an emeritus professor at the University of Illinois at Urbana-Champaign.

Though there was no official confirmation of the news, his demise was reported on Twitter by Professor Vipin Narang, another authority on South Asian affairs.

'I just learned that Stephen P. Cohen, a pioneer and giant in the South Asia security field and mentor [of] so many of us, passed away this morning. I will never forget his encouragement and support to me, a nobody graduate student. Rest In Peace Professor Cohen,' wrote Narang, who is also an expert in nuclear proliferation and strategy and North Korean nukes.

Cohen was named as one of America's 500 most influential people in foreign affairs, and a fixture on radio and television talk shows.

He authored, co-authored or edited at least 12 books which included Shooting for a Century: The India-Pakistan Conundrum; The Future of Pakistan; The Idea of Pakistan; The Compound Crisis of 1990: Perception, Politics, and Insecurity; India: Emerging Power; The Pakistan Army: with a new foreword and epilogue...