1990, the Syrian occupation of Lebanon continued until they themselves were also forced out by widespread public protest and international pressure. About 20,000 Syrian soldiers were deployed in Lebanon until 27 April 2005, when the last of Syria's troops left the country. Syrian forces have been accused of involvement in the murder of Rafiq al-Hariri, as well as continued meddling in Lebanese affairs, and an international investigation into the Hariri killing and several subsequent bomb attacks has been launched by the UN. Other engagements Engagements since 1979 have included the Muslim Brotherhood insurgency (1979–82), notably including the Hama massacre, the 1982 Lebanon War (against Israel) and the dispatch of the 9th Armored Division to Saudi Arabia in 1990–91, ahead of the Gulf War against Iraq. The 9th Armored Division served as the Arab Joint Forces Command North reserve and saw little action. Syria's force numbered ~20,000 in strength (the sixth-largest contingent) and its involvement was justified domestically as an effort to defend Saudi Arabia. Syria's initial involvement in Operation Desert Shield also rolled into the Allied Operation Desert Storm, as Syrian forces did participate in helping dislodge and drive Iraqi forces out of Kuwait City. Total losses sustained were two dead and one wounded. There were indications the Syrian government had been prepared to double its force to 40,000. Modernisation In recent years Syria has relied on Russian arms purchases to obtain modern weapons. Purchases have included anti-tank and air defense systems. In early September 2008 the Syrian government ordered MiG-29SMT fighters, Pantsir S1E air-defence systems, Iskander tactical missile systems, Yak-130 aircraft, and two Amur-1650 submarines from Russia. Russia's Foreign Minister Sergei Lavrov asserted that the sale wouldn't upset the balance of power in the Middle East and were "in line with . . . international law." Russia aims to turn the Russian naval base in Tartus into a permanent base. Israel and the US oppose further arms sales to Syria due to fears that the weapons could fall under the control of Iran or Hezbollah fighters in Lebanon. Syrian Civil War Because of the violence against the people by the Syrian Army and the detention of a great number of people, some soldiers from different religions and sects (Sunni, Shia, Druze and Christian) defected in protest at orders to kill protesters in April 2011. By 2014, the number of defecting officers had reached approximately 170,000, from different ranks. They