ahead of operation dawn-4, units of the 1st corps spent two months in their trenches waiting for the iranians to attack. the offensive came on 19 october 1983 as the iranians and peshmerga guerrillas of the patriotic union of kurdistan took of territory. this included a number of kurdish villages and exerted a significant amount of pressure on penjwin. saddam hussein responded with a counterattack, using the iraqi republican guard and poison gas. however, they failed to dislodge the iranians, who were dug-in and reinforced by kurdish fighters.