Iraqi offensive and Iranian push back

In September 1980 the Iraqi army carefully advanced along a broad front into Khūzestān, taking Iran by surprise. Iraq’s troops captured the city of Khorramshahr but failed to take the important oil-refining centre of Ābādān. By December 1980 the Iraqi offensive had bogged down about 50–75 miles (80–120 km) inside Iran after meeting unexpectedly strong Iranian resistance. The zeal of the Islamic Revolutionary Guards Corps (IRGC).