The head of the defense committee in Russia's upper house of parliament has estimated that about 1,000 Russian military personnel will remain in Syria at Russia's two bases. The head of the parliamentary defense committee, Viktor Ozerov, said Tuesday that he estimated about 1,000 Russian military personnel would remain in Syria at the two bases. That's according to the Interfax news agency. Ozerov says Russia would need a minimum of two battalions, a total of 800 troops, to protect the two bases. He says it will continue to conduct air reconnaissance, requiring some of the plane crews to remain, and the military specialists advising the Syrian army also would stay. The estimate follows President Vladimir Putin's announcement Monday that some of the Russian aircraft and troops would be withdrawn. Russia has not revealed how many soldiers it has deployed to Syria, where it maintains a naval facility as well as an air base, but U.S. estimates of the number of Russian military personnel varies from 3,000 to 6,000.