extremely tough fight, but eventually the Iraqis called off their attack to regroup; at noon the Israelis were reinforced by another battalion. This new balance of combat power lead the exhausted and bloodied Iraqis to decide they did not possess the strength to dislodge the Israelis, and they retired from the field. After these defeats, the ALA took several months to resume operations, but by then most of its Iraqi contingent had joined the main Iraqi expeditionary force that had arrived in northern Samaria. The first Iraqi forces of the expeditionary force reached Transjordan in early April 1948, with one infantry brigade and a supporting armoured battalion under the command of General Nur ad-Din Mahmud. On 15 May, Iraqi engineers built a pontoon bridge across the Jordan River, allowing the combat units to cross into Palestine. Over 3,000 Iraqi soldiers with armor and air support were unable to defeat less than 50 lightly armed Jewish defenders. After the crossing, the Iraqis immediately launched a frontal assault against the Israeli settlement of Gesher, only to be quickly driven back. The Iraq army tried again the next day, with their armour attacking from the south and their infantry from the north. The double envelopment was poorly implemented - lacking infantry-tank coordination - which left the Israelis with the breathing space to redeploy their small force along internal lines and defeat each attack in turn. The Iraqis launched clumsy frontal assaults, with the unprotected tanks and armoured cars being easily destroyed by AT hunter-killer teams. Several days later, Mahmud tried to attack another Jewish settlement in the same area, but the troops didn't scout their route properly and got ambushed before they could even reach the target settlement. These defeats convinced the Iraqi army to abandon this sector of the front and try their luck elsewhere. The expeditionary force moved into the Nablus–Jenin–Tulkarm strategic triangle in May, that being the West Bank region of northern Samaria. That was a key sector for the Arab war effort because it was the ideal jumping point for an attack westward against Haifa to split the narrow Israeli corridor along the Mediterranean coast (which was only 15 km wide) and break the country in half; it would also guard the right flank of the Transjordanian Arab Legion, which was concentrated to the south, around the Jerusalem corridor. Previously, this sector had been held by elements of the