The incident, which took place at main entrance to the campus, takes the number of professors murdered since the U.S.-led invasion of the country to 58.

“Unidentified people shot and killed Dr. Zaki al-Ani from the College of Arts and Dr. Hashem Abdulamir from the College of Education,” a university source told the newspaper on condition of anonymity.

The third professor, Dr. Sameer Yalda of the College of Economics and Administration, was kidnapped as he left the university and his body was found dumped on a main street in Baghdad.

The incentives behind the killings are not known.

And the police have not yet solved the mystery behind any of the previous 55 murders of Iraqi university professors.

As a result, Iraqi professionals are leaving in droves.

Statistics by the Ministry of Higher Education and Scientific Research show that more professors have left the country since the U.S. invasion than under the reign of former leader Saddam Hussein.