Battle of the Marshes The Battle of the Marshes was a part of the Iran – Iraq War . After the relatively unsuccessful Dawn Operations in 1983 , Iran opened a new offensive in the lakes of the Hawizeh Marsh in Iraqi Tigris - Euphrates river system . After heavy losses at the beginning due to human wave attacks , 15 , 000 casualties and little progress , Iran began developing new tactics , involving amphibious assault , and deployed a regular army division : The 92nd Armored Division . Although the Iranians suffered heavy losses against the Iraqi artillery , tanks , air strikes and gunboats , Iran eventually managed to invade the oil rich Majnoun Islands with Operation Kheibar and nearly break the Iraqi lines before being driven back to the marshes and Majnoon Island . Prelude and Iranian tactics . After the mostly indecisive Dawn Operations , Iran attempted to change tactics . Iran had launched numerous operations in 1983 around Basra and southern Iraq using massed human wave attacks , but they faced limited successes in the face of the Iraqi static defense s . In addition , the Iraqis began launching counterattacks . In the face of increasing Iraqi armament and manpower as well as increasing problems on their own side , Iran could no longer rely on outnumbering Iraqi troops . While the infantry and human wave assaults would remain key to their attacks throughout the war , Iran began to rely more heavily on deception surprise attacks , as well as light infantry warfare . In contrast to Iraq ' s static defences and heavy armour , Iran began training troops in infiltration , patrolling , night - fighting , marsh warfare , and mountain warfare . They also began training thousands of Revolutionary Guard commandos in amphibious warfare , as southern Iraq is marshy and filled with wetlands . Iran used speedboats to cross the marshes and rivers in southern Iraq , landing troops on the opposing banks , where they would dig and set up pontoon bridges across the rivers and wetlands to allow heavy troops and supplies to cross . Transport helicopters were used as well , ferrying troops to the battlefield . Iran ' s amphibious assault tactics , using Boghammar speedboats as landing craft would be decisive during this battle . Iraqi tactics . By the end of 1982 , Iraq had been resupplied with new Soviet material , and the ground war entered a new phase . Iraq used newly acquired T - 55 tanks and T - 62 tanks , BM - 21 Stalin Organ rocket launchers , and Mi - 24 helicopter gunships to prepare a Soviet - type three - line defense , replete with obstacles , minefields , and fortified positions . The Combat Engineer Corps built bridges across water obstacles , laid minefields , and prepared new defence lines and fortifications . [ 6 ] : 2 In order to defend Basra , the Iraqis poured water into a pre - existing lake east of Basra , known as Fish Lake , and filled it with barbed wire , floating land mines , and high voltage electrical power lines to make it impenetrable to the Iranians . [ 45 ] They also began launching air raids against Iranian border cities , greatly increasing the practice by 1984 . With such static defenses , the Iraqis had effectively made frontal assault through the flat lands virtually impossible for the Iranians . Thus the Iranians would launch their amphibious attacks . Diversionary Attacks . Prior to the attack , the Iranian commandos on helicopters landed behind Iraqi lines , and even destroyed Iraqi artillery . Iran launched two preliminary attacks prior to the main offensive , Operation Dawn 5 and Dawn 6 . They saw the Iranians attempting to capture Kut - al - Imara , Iraq and sever the highway connecting Baghdad to Basra , which would impede Iraqi coordination of supplies and defences . The area , located on a large waterway , had been considered impenetrable by Iranians , but Iranian troops crossed the river using Boghammar speedboats in a surprise attack . However , the Iranian forces only came within of the highway . Afterwards , Iran began Operation Kheibar , the main offensive . Operation Kheibar . By 1984 , the Iranian ground forces were reorganised well enough for the Revolutionary Guard to start Operation " Kheibar " , which lasted from 24 February to 19 March . Beginning on 15 February 1984 the Iranians started launched attacks against the central section of the front , where the Second Iraqi Army Corps was deployed , with 250 , 000 Iraqis facing 250 , 000 Iranians . Operation Kheibar began on 24 February began Iranian infantrymen crossed the Hawizeh Marshes using speedboats in an amphibious assault . This took the Iraqis by surprise , since the marshes were considered impenetrable , and worse the Iraqi could not use their tanks . The marshes also absorbed the impact of Iraqi artillery and bombs . The Iranians attacked the vital oil - producing Majnoon Island by landing troops by helicopters onto the islands and severed the communication lines between Amareh and Basra . The Iranians continued the attack towards Qurna . Iraqi defences , under continuous strain since 15 February , seemed close to breaking . However , they were saved by their use of chemical weapons and defence - in - depth , where they layered several defensive lines ; even if the Iranians broke through the first line , they were usually unable to break through the second due to exhaustion and heavy losses . Iran suffered also from a shortage of air and armour and the infantry had to bear the brunt of the fighting . The Revolutionary Guard also used guerrilla tactics in the marshes blending into the terrain and bypassing the Iraqis . Iranian mounted infantry using motorcycles also pushed deeper into Iraqi lines . The Iraqis heavily used Mi - 25 Hind to " hunt " the Iranian troops in the marshes , killing many soldiers . On 27 February , Iran finally captured Majnoon Island , but lost 49 of their own helicopters shot down by Iraqi fighters . Fighting took place in waters over 2 meters deep at times . Iraq in response to the attacks ran live electrical cables through the water , electrocuting numerous Iranian troops and then displaying their corpses on state television . By 29 February , they had reached the outskirts of Qurna and nearly reached the Baghdad - Basra highway . But by this time , the Iranians had broken out of the marshes and returned to open terrain , and were confronted by the conventional Iraqi forces including artillery , tanks and air power , and also mustard gas as well . 1 , 200 Iranian troops were killed in the counterattack . The Iranians were forced to retreat back to the marshes , however they still held onto them along with Majnoon Island . The Iraqis ' heavy use of chemical weapons halted the Iranian advance on Basra , thought they failed to retake Majnoon . At least 20 , 000 Iranians were killed in the fighting in the marshes , with Iraqi helicopter gunships being deployed to " hunt " the Iranian troops through the swampy land . The Iranians also used combined helicopter and riverboat operations as part of this attack , known as the Fatima al - Zahra operations ( named after the daughter of Prophet Muhammad ) , charting and mapping all of the marshes . Aftermath . Although the Iranians suffered greater losses , their large numbers enabled them to continue . Iraq ' s 4000 casualties , on the other hand , severely inhibited its ability to continue . Iraq was relying on Soviet tanks and artillery and air support . Iran , with three times the size and population of Iraq , relied on sheer numbers due to turmoil caused by the recent revolution that negatively affected the amount of military organization , trade , supplies , and equipment ; they were victorious despite somewhat inferior equipment .