In a much-anticipated report , the United Nations has concluded that chemical weapons have been used in the Syrian conflict . Experts investigated seven instances of alleged use and found that chemical weapons were either used , or likely used , in five of those instances . The case that was most clear to inspectors was an August incident near the capital , Damascus . `` The United Nations Mission collected clear and convincing evidence that chemical weapons were used also against civilians , including children , on a relatively large scale in the Ghouta area of Damascus on 21 August 2013 , '' read the 82-page report , which was released on Thursday . Blood and urine samples from patients there tested positive for sarin and sarin signatures , it found . Anti-government activist groups say more than 1,300 people were killed in the attack in Ghouta -- many of them women and children . Graphic video footage showed rows of bodies without apparent injury , as well as people suffering convulsions or apparently struggling to breathe . U.N. inspectors also said they collected credible information , or evidence consistent with the probable use of chemical weapons , in Khan al Asal , Jobar , Saraqueb and Ashrafiah Sahnaya . They were unable to corroborate the allegation that chemical weapons were used in either Bahhariyeh or Sheik Maqsood . The report did not specify whether the government or opposition groups were responsible for the alleged attacks , which happened between March and August this year . The United Nations estimates that more than 100,000 people overall have died since the Syrian conflict began in March 2011 . It began with a government crackdown on peaceful protesters during the Arab Spring movement , then slowly spiraled into a bloody , full-blown civil war . Rebel leader denies he fled . Also Thursday , a top Syrian rebel commander denied that he had abandoned his post and said he is working to resolve fighting among opposition groups in the country 's north . In the meantime , a decision by the United States and Britain to halt nonlethal aid makes sense , said Salim Idriss , chief of staff of the Free Syrian Army . Several U.S. administration officials had said that the fate of Idriss , a top rebel commander supported by the West , was uncertain as conflicts persisted between the Free Syrian Army and Islamist groups . Idriss denied reports that he fled to a Gulf state after the Islamic Front allegedly seized a warehouse held by the Free Syrian Army . He did leave Syria , but is working at his office on the Turkish border and has not left his job , Idriss told CNN . In this case , he was already in Turkey when the attack on the warehouse happened , he said . On Wednesday , Turkey sealed its border with Syria because of the fighting between opposition groups in Syria . In the past two days , Idriss has been talking with different groups and has tried to resolve their differences , he said . `` The situation in the north of Syria now is very complicated and very dangerous because there are some problems between some groups , and I think we will try and we should try everything now to find a solution for this problem , '' he said . The Islamic Front , which announced its formation last month , is an alliance that includes tens of thousands of fighters from some of Syria 's most powerful Islamist groups , including Ahrar al-Sham , Suqour al-Sham , the Islamic Army and the Tawhid Brigade . The groups control territory in key areas across Syria and have been fighting forces loyal to President Bashar al-Assad along the critical lines of Damascus and Aleppo , among other places . The front 's formation has diminished the stature of the Western-backed Free Syrian Army and its leadership abroad , the Syrian National Coalition , as leaders inside the country have sought to distance themselves from a command structure criticized for failing to serve the opposition 's needs on the ground . 'Infighting is growing ' The seizure of the warehouse this week could prove key in shaping how the United States deals with the Syrian opposition . `` The Syrian opposition has never been a unified fighting force but infighting is growing and , naturally , this is hindering cooperation on the battlefield , '' said one U.S. official . `` At least temporarily , there will be more turbulence within the opposition as the new groups that have cropped up compete for power . What is n't clear yet is whether the various factions will refocus attention on toppling Assad or become embroiled in internecine fighting that would play to the regime 's advantage . '' According to Idriss , the Islamic fighters did not take over the warehouse , but attacked a Free Syrian Army battalion that was protecting it and took its inventory . It was unclear which group gave the orders to attack the battalion , he said . The inventory that was inside the warehouse -- which was not American aid , Idriss said -- is in good shape and will hopefully be returned . Idriss admitted that he does n't fully trust the Islamists , but that an agreement must be reached to control the fighting and form a single command . The fighting among these groups opposed to al-Assad led the United States and Britain to suspend nonlethal aid to the rebel groups . `` It is very difficult now to pass the support to the right hands . And that 's why I can understand the , let me say , freezing the support for a period of time , '' Idriss said . The Supreme Military Council of the Free Syrian Army called the allegations that Idriss had abandoned his post rumors . `` Such rumors only serve to impact on the morale of our brothers fighting on the ground at a time when we need to concentrate on stopping the criminal regime , which continues to perpetrate horrific massacres all over the country against our people , '' the council said in a statement .
The United Nations releases a much-anticipated report . It finds `` convincing evidence '' that such weapons were used against children . The report does not say who is responsible for the attacks .