A firing squad of the Islamic State has executed at least 300 Iraqi civil servants, including some 50 women, who worked for the election commission, a media report said.The mass killings on Saturday took place at a military camp in the Iraqi city Mosul, EFE reported.A military official said at least 50 of those shot dead were women. The Electoral Commission said in a communique that the IS terrorists slit the throats of another group of its employees in Mosul.