The main attack began on 5 January.
The attack began with a short artillery bombardment.
The Iranian forces, using pontoon bridges, crossed the Karkheh River.
The Iranians used 300 tanks.
Due to the muddy terrain, they were confined to the paved road.
Because of that, the Iranians assembled their forces in a long row of columns.
The first three columns consisted of armored brigades, and the final column was the infantry support.
The infantry was thus behind the tanks, and the entire flank of this long row of column was completely exposed.

The Iranian forces began to move down the paved road which ran between Ahvaz and Susangerd.
 They moved very slowly, and each column moved separately.
 Unknown to the Iranians, their plans had already begun to go awry when Iraqi observation aircraft spotted the column moving west towards Susangerd.
 Thus their plans for surprise had been foiled.
 The Iraqis immediately began planning their action.
The Iraqis moved their 10th Armored Brigade, and positioned them on the Iranian line of advance on the road.
 The Iraqis dug their tanks into a hull-down position, meaning they were dug into the mud and used as static pieces.
 While the Iraqis often lacked the skill to maneuver, and regularly put their tanks in dug-in positions gaining the advantage of a smaller/lower silhouette, in this instance it would prove to be successful, because the extremely muddy conditions would hamper armored maneuver.
 The Iraqi tanks (Soviet T-62) and (Soviet T-72) were dug into positions both in front of and on the side of the Iranian line of advance.
 The Iraqis were also supported by attack helicopters such as Mi-8s, BO-105s, Alouette IIIs, and Sa-341/342 Gazelles.
 Thus the Iraqi trap was set.

On 6 January, the next day,  Iranian forces came into contact with the Iraqi armor.
Iran's shortage of reconnaissance proved to be disastrous as they failed to see the approaching trap.
The Iraqis began firing at the Iranian tanks from the front and both sides.
The Iranians tried to drive through the Iraqi forces in an armored spearhead, but took heavy losses.
They then tried to maneuver.
But that involved driving their tanks off the paved road, and into the mud.
 Iranian tanks then got stuck in the mud.
The first Iranian brigade was decimated, and many tanks were destroyed or abandoned in the mud.
Nevertheless, the Iranians refused to abort the attack, and their next brigade moved into action.

The second Iranian brigade advanced, and the results were similar.
Iranian helicopters (AH-1J SeaCobras) also joined the battle, destroyed several dug-in Iraqi tanks, but their efforts were not enough to alleviate the pressure on the Iranian ground force and the Iranian armor kept taking heavy losses.
The Iraqis also had anti-aircraft weapons, and several Iranian helicopters were shot down.
To make matters worse, Iraqi mechanized infantry with anti-tank weapons joined in, turning the battle into a slaughter for the Iranians.
Fighting took place at close range and was brutal.
Just when things were going badly, Iraqi aircraft also bombed the pontoon bridge across the Kharkeh River, trapping the Iranian tanks and preventing their retreat.
Iran's infantry was also stuck on the opposite bank (they hadn't moved into action yet) and separated from joining the battle.
Iranian helicopters attempted to fight back, but they were attacked by Iraqi fighter jets, which  destroyed  or damaged several helicopters.

By 8 January, the entire Iranian attack was in chaos.
Many tanks from the first two brigades had been lost, either destroyed, or stuck in the mud and abandoned.
The third Iranian brigade attempted to continue the attack, but could make little headway.
Instead, Operation Nasr was aborted, and the Iranians moved to retreat.
The infantry force (which never had a chance to join the battle) instead moved into a defensive position to prevent an Iraqi counterattack.
 Iranian engineers at the last second managed to rebuild the pontoon bridges over the Karkheh river, and the third Iranian tank brigade managed to break away from the combat and r
The main attack began on 5 January. The attack began with a short artillery bombardment. The Iranian forces, using pontoon bridges, crossed the Karkheh River. The Iranians used 300 tanks. Due to the muddy terrain, they were confined to the paved road. Because of that, the Iranians assembled their forces in a long row of columns. The first three columns consisted of armored brigades, and the final column was the infantry support. The infantry was thus behind the tanks, and the entire flank of this long row of column was completely exposed.
The Iranian forces began to move down the paved road which ran between Ahvaz and Susangerd.  They moved very slowly, and each column moved separately.  Unknown to the Iranians, their plans had already begun to go awry when Iraqi observation aircraft spotted the column moving west towards Susangerd.  Thus their plans for surprise had been foiled.  The Iraqis immediately began planning their action. The Iraqis moved their 10th Armored Brigade, and positioned them on the Iranian line of advance on the road.  The Iraqis dug their tanks into a hull-down position, meaning they were dug into the mud and used as static pieces.  While the Iraqis often lacked the skill to maneuver, and regularly put their tanks in dug-in positions gaining the advantage of a smaller/lower silhouette, in this instance it would prove to be successful, because the extremely muddy conditions would hamper armored maneuver.  The Iraqi tanks (Soviet T-62) and (Soviet T-72) were dug into positions both in front of and on the side of the Iranian line of advance.  The Iraqis were also supported by attack helicopters such as Mi-8s, BO-105s, Alouette IIIs, and Sa-341/342 Gazelles.  Thus the Iraqi trap was set.
On 6 January, the next day,  Iranian forces came into contact with the Iraqi armor. Iran's shortage of reconnaissance proved to be disastrous as they failed to see the approaching trap. The Iraqis began firing at the Iranian tanks from the front and both sides. The Iranians tried to drive through the Iraqi forces in an armored spearhead, but took heavy losses. They then tried to maneuver. But that involved driving their tanks off the paved road, and into the mud.  Iranian tanks then got stuck in the mud. The first Iranian brigade was decimated, and many tanks were destroyed or abandoned in the mud. Nevertheless, the Iranians refused to abort the attack, and their next brigade moved into action.
The second Iranian brigade advanced, and the results were similar. Iranian helicopters (AH-1J SeaCobras) also joined the battle, destroyed several dug-in Iraqi tanks, but their efforts were not enough to alleviate the pressure on the Iranian ground force and the Iranian armor kept taking heavy losses. The Iraqis also had anti-aircraft weapons, and several Iranian helicopters were shot down. To make matters worse, Iraqi mechanized infantry with anti-tank weapons joined in, turning the battle into a slaughter for the Iranians. Fighting took place at close range and was brutal. Just when things were going badly, Iraqi aircraft also bombed the pontoon bridge across the Kharkeh River, trapping the Iranian tanks and preventing their retreat. Iran's infantry was also stuck on the opposite bank (they hadn't moved into action yet) and separated from joining the battle. Iranian helicopters attempted to fight back, but they were attacked by Iraqi fighter jets, which  destroyed  or damaged several helicopters.
By 8 January, the entire Iranian attack was in chaos. Many tanks from the first two brigades had been lost, either destroyed, or stuck in the mud and abandoned. The third Iranian brigade attempted to continue the attack, but could make little headway. Instead, Operation Nasr was aborted, and the Iranians moved to retreat. The infantry force (which never had a chance to join the battle) instead moved into a defensive position to prevent an Iraqi counterattack.  Iranian engineers at the last second managed to rebuild the pontoon bridges over the Karkheh river, and the third Iranian tank brigade managed to break away from the combat and r
Operation Nasr