The Franks sent messengers  to Al-Ashraf Khalil who saluted him on their knees. Khalil asked them whether they brought him the keys of the city, but they replied that the city could not be surrendered so easily and that they only came to plea for mercy for the poor inhabitants and that the Franks were willing to discuss any injustice done by them earlier to the Muslims and to restore the truce signed by them and the Muslims. Khalil promised the messengers to spare the life of everyone if the Franks hand him Acre peacefully but the messengers refused his offer . While the messengers were still there a huge catapult stone launched from the city struck the ground near the sultan's tent. Khalil, believing that the crusaders were negotiating in bad faith, reacted furiously and wanted to kill the two messenger but Emir Sanjar al-Shuja' pleaded for them and they were sent back to the city.
From May 8, Acre's towers began to cave in one after one. On May 18, early in the morning at sunrise, the Sultan gave his order to launch an all-out attack on all points, accompanied by sound of trumpets and drums carried on 300 camels . The Muslim forces advanced towards a great tower that was called the Accursed Tower  and forced the Frankish garrison to retreat to the side of the Gate of St. Anthony. Muslim standards were placed on the walls. All counter-attacks and attempts made by the Hospitallers and the Templars to recapture the tower were in vain. King Henry II and the Master of the Hospital boarded their galleys and fled from Acre  William of Beaujeu, the Master of the Temple, and Matthew of Clermont were killed. By capturing these positions, the Muslim forces were now inside the city fighting the Franks in the streets and alleys of Acre, which turned into a terrifying chaos as the inhabitants were fleeing towards the sea. How many inhabitants perished on land and in sea is unknown. "More than five hundred most noble ladies and maidens, the daughters of kings and princes, came down to the seashore, when the city was about to fall, carrying with them all their jewels and ornaments of gold and precious stones, of priceless value, in their bosoms, and cried aloud, whether there were any sailor there who would take all their jewels and take whichever of them he chose to wife, if only he would take them, even naked, to some safe land or island" Ludolph of Suchem described . Before night, Acre, after being in the hands of the Franks for 100 years , was in the hands of Al-Ashraf Khalil and his army after a siege of 43 days, with exception of the huge headquarters of the Templars which stood on the west side of the city seashore. After a week, Al-Asraf Khalil negotiated with Peter de Severy, who was in charge of the Templars, and it was agreed that the Templars and everyone inside the fortress would have free passage to Cyprus, but the Sultan's men who were sent to the fortress to supervise the evacuation seemed not disciplined enough to handle the matter and were massacred by the Templars. Under the cover of darkness, Theobald Gaudin, the new Master of the Temple, left the fortress for Sidon with a few people and the fortune of the Templars. In the morning, Peter de Severy went to the Sultan to settle a new negotiation but he was arrested with his followers and they were executed in retaliation for the Sultan's men who were masscared earlier by the Templars inside the fortress. When the besieged Templars in the fortress saw what happened to Peter de Severy, they continued the fight. On May 28, after a wide breach was made under the fortress, the Sultan sent about 2000 men to take it. The Frankish fortress collapsed killing everyone inside, including Sultan's men .
The news of the conquest of Acre reached Damascus and Cairo. Al-Ashraf Khalil entered the decorated city of Damascus with Franks chained at the feet and the captured crusader standards which were carried upside-down as a sign of their defeat. After celebrating his victory in Damascus, Khalil left for Cairo which was also decorated and celebrating . Arriving at Cairo, he ordered the release of Philip Mainebeuf and the men who accompanied him to Cairo earlier .
Capture of Tyre, Sidon, Beirut, Haifa and Tartus
The port of Tyre was one of the most protected strongholds of the Franks on the Syrian coast. Saladin failed twice to capture it. Tyre was passed from Margaret of Lusignan  to her nephew Amalric shortly before the capture of Acre by Al-Ashraf Khalil. On May 19, Al-Ashraf, while still in Acre, sent a group of men, led by Emir Sanjar al-Shuja'i, to examine the situation in Tyre. Having a small garrison and seeing the fleeing refugees from Acre, Adam of Cafran, the Bailli of Tyre, panicked and fled to Cyprus. Tyre was taken by the Muslims without a fight.
A month after the capture of Acre, Al-Ashraf Khalil sent a force led by Emir al-Shuja'i to Sidon. The Knights Templar, as their fortune had been brought to Sidon earlier by Theobald Gaudin, the new Master of the Temple, decided to take refuge inside a castle that was built on an isle ca. 90 meters from the shore. Gaudin took the fortune and left for Cyprus after he promised his followers to send reinforcement from Cyprus. But Gaudin never sent anything and his followers had to fight till they fled by sea, in the night, to Tartous after they saw the Muslims building a bridge. Emir al-Shuja'i ordered the destruction of the sea castle on July 14 .
After the capture of Sidon, al-Shuja'i marched to Beirut. Beirut, which had a small garrison, was an important trading seaport for the Crusaders. Eschiva of Ibelin, the Lady of Beirut, thought she was secure because she had a truce with al-Ashraf Khalil's father Qalawun. al-Shuja'i summoned the commanders of the garrison and arrested them. Seeing the commanders arrested, everyone fled by sea. Beirut was taken by the Muslims on July 31. al-Shuja'i ordered the razing of its walls and castles and turned its Cathedral to a Mosque.
Haifa was captured on July 31, with little resistance. Tartus was besieged by Emir Bilban and the crusaders had to flee to the nearby island of Arwad  and was captured on August 3, followed by Atlit on August 14. Nothing was left for the Franks except the Island of Arwad which was captured by an Egyptian army later in 1302 .
In 1292, Al-Ashraf Khalil accompanied by his Vizier Ibn al-Salus arrived to Damascus and left - via Aleppo - to besiege the castle of Qal'at ar-Rum (Hromgla in Armenian). Qal'at ar-Rum, which was the seat of the Patriarch of Armenia, was besieged by more than 30 catapults  and was captured after 30 days by Khalil, who renamed it Qal'at al-Muslimin (Castle of the Muslims) . Khalil left Emir al-Shaja'i at the castle and returned to Damascus with prisoners. The population of Damascus bid farewell to the victorious Sultan on his way to Cairo at night with thousands of lighted candles. The Sultan entered Cairo from the Victory Gate (Bab al-Nasr) and was greeted by the celebrating population, also with thousands of lighted candles .
The Sultan returned to Damascus and assembled an army to invade Sis , the capital of the Armenian Kingdom of Cilicia, but Armenian messengers arrived to Damascus and appealed to him not to attack Sis. Til Hemdun, Marash and Behesni were given to the Sultan in exchange for peace. On the other hand, Khalil had good relations with the Kingdom of Cyprus, the Kingdom of Aragon, and the Kingdom of Sicily, who had commercial and military treaties with him.
The process of conquering the crusader kingdom, begun by Saladin in 1187, was finally completed by . Al-Ashraf Khalil who was also planning to attack Cyprus  and the Mongols in Baghdad .
The Crusaders were shocked. Their 200 years of effort had gone in vain. The crusaders' kingdom of Jerusalem had already been destroyed by Saladin, Baibars and Qalawun, and Louis IX's Seventh Crusade against Egypt ended in a complete failure, but the crusaders tried to keep their strongholds on the Syrian coast intact, hoping to be able one day to recapture what they had lost. Pope Nicholas IV tried to act but he died in 1292  , and the European kings, who became involved in internal conflicts and struggles , became unable to organize new effective crusades. As for the Templars, they were accused of heresy in Europe and badly persecuted by King Philip IV of France and Pope Clement V.