Syrian Ambassador to Lebanon Ali Abdel Karim Ali has expressed concern over the infiltration of foreign - backed militants into Syria from the Lebanese border.In a Saturday television interview, Ali said that Lebanon has opened its border to the members of the terrorist group al-Nusra Front and the terrorist Free Syrian Army and al-Qaeda groups, and the militants have an extensive presence in the Lebanese cities of Tripoli and Akkar. The Syrian diplomat noted that the Lebanese officials should have taken action against the issue as the militants are violating the territorial integrity of both Lebanon and Syria. Ali pointed out that the Syria will definitely respond to the individuals who open fire at the Syrian checkpoints and police offices or seek to infiltrate into the Syrian territory. The Syrian diplomat said that such anti-Syria measures will also negatively affect the Lebanese government and army, which are opposed to the ongoing situation against Damascus. Ali stated that al-Nusra front and all the extremist groups are being supported by Qatar, Turkey, the US and Israel and that Washington is determined to destroy Syria. New video footage, which was posted online on Saturday, shows foreign-backed militants ransacking shops and homes in the city of Dara’a in southwestern Syria and Aleppo in the northwest of the country. The militants have attacked and destroyed several holy sites, including Shia mosques and shrines, since the beginning of the unrest in Syria. The crisis in Syria began in March 2011, and many people, including large numbers of Syrian soldiers and security personnel, have been killed in the violence. The Syrian government says that the chaos is being orchestrated from outside the country, and there are reports that a very large number of the militants are foreign nationals.