Gunmen have killed some 182 Iraqi university professors and academics since the U.S. invasion in early 2003 and a group representing Iraqi academia said on Thursday the killings constituted a war crime.

Another 85 senior academics have been kidnapped or survived assassination attempts, according to the Association of University Lecturers in Iraq.

The attacks have led to an exodus of Iraqi academics who are vital to educating and rebuilding the war-damaged country.

"What is going on in Iraq against these professors is a real war crime," said Dr Isam Kadhem Al-Rawi, head of the association and Professor in Earth Sciences at the University of Baghdad.