Syrian security officials confirmed that the armed opposition militants have locally manufactured land-to-land rockets in addition to sarin gas, in the wake of the UN report on a chemical weapons attack on Damascus last month. \"I deny a hundred percent the use of the material by the Syrian army,\" the Syrian official said in the first official reaction after the report. \"There is no justification to resort to this weapon because we are achieving victories on the ground,\" he stated, noting that \"those who resort to this weapon is the defeated party who have reached the point of suicide\", the Islam Times reported. The source indicated that the Syrian army \"is making progress in all areas, and operations are going according to the plan\". The official also underlined that \"the terrorists manufacture land-to-land rockets locally, and it is likely that they have put sarin gas in them\", in reference to the Ghouta alleged attack in August 21. \"The terrorists know perfectly well how to mount the material on missile warheads,\" the Syrian official said, adding that they had \"received training at the hands of the US, British and French intelligence experts who are working with them on the ground\". On Tuesday, a senior Russian diplomat said that the Syrian authorities have handed over to Russia evidence proving that opposition forces were involved in the use of chemical weapons last month. Russian Deputy Foreign Minister Sergei Ryabkov said on Tuesday night after the meeting with Syrian Foreign Minister Walid Mualem in Damascus that \"this evidence must be analyzed\". UN inspectors said Monday that they had found \"clear and convincing evidence\" that chemical weapons, including the nerve agent sarin, were used in an August 21 attack that killed hundreds of people in the Damascus suburb of Ghouta. The inspectors had no mandate to determine who had launched the attack - which the US and some of its western allies have attributed to the government of Syrian President Bashar al-Assad, but Moscow and Syria have called it a provocation by anti-Assad rebels. The diplomat added that Moscow was \"disappointed\" with the way the UN mission of experts in Syria approached the report and called it as \"incomplete\". Russian Foreign Minister Sergei Lavrov said on Tuesday the report did not answer many questions and called for additional UN investigations into allegations of chemical weapons use in Syria. The US position that the Syrian army was behind the August 21 attack had prompted Washington to threaten \"limited\" retaliatory military strikes against Syria. This plan was put on hold last week after Lavrov put forward a proposal, based on off-the-cuff comments by US Secretary of State John Kerry, that a strike could be avoided if Syria were to put its chemical weapons under international control. On Saturday, after days of intense negotiations, Lavrov and Kerry announced an ambitious plan under which all chemical weapons in Syria would be opened up to international inspectors by November and destroyed by mid-2014.