( CNN ) -- A team of U.N. chemical weapons inspectors are in Syria where they will begin an investigation Monday into whether chemical weapons have been used during the bloody civil war there . The team wo n't be speaking to reporters during the visit , it said in a written statement , U.N. Secretary-General Ban Ki-moon 's office said . Syria has been embroiled in a war for more than two years , during which more than 100,000 people have been killed and millions have been displaced or become refugees in other countries , according to the United Nations . Amid the fighting , there have been numerous allegations that chemical weapons have been used . Syria strikes refugee camp in northern Lebanon . In June , the White House said Syrian President Bashar al-Assad 's forces had crossed a `` red line '' by using chemical weapons , including the nerve agent sarin gas , against rebel forces . This prompted the U.S. government to begin providing military support to opposition fighters , despite its earlier reluctance to do so . Bashar al-Assad is all smiles on his new Instagram account . Syria 's government , meanwhile , has claimed rebel fighters have used chemical weapons as well . That includes a March incident in Khan al-Asal in the northern province of Aleppo , according to state media . Opposition officials have said rebels do n't have access to chemical weapons or the missiles needed to use them in an attack , while other rebel leaders said Syrian troops fired `` chemical rockets '' at civilians and opposition forces . Chemical weapons frightful , relatively inexpensive . The government has agreed to arrangements `` essential for cooperation to ensure the proper , safe and efficient conduct of the mission , '' the secretary-general 's office said last week . Khan al-Asal will be one of the three incidents that U.N. inspectors will look into , a U.N. spokesperson said in late July . Global Public Square : What Iraq could teach us about Syria .
The Syrian government has agreed to the terms of visit . The U.S. says Syrian forces crossed a ` ` red line '' by using chemical weapons . The Syrian government denies they have used them .