
CEYLANPINAR, Turkey — Russia said on Tuesday that its military units were patrolling territory in northern Syria vacated by the Americans following the withdrawal ordered by President Trump, underscoring the sudden loss of United States influence in the eight-year-old Syria war.
The Americans had until Monday maintained two military bases in the area, and Russia’s announcement signaled that Moscow, the Syrian government’s most important ally, was moving to fill a security void left by the withdrawal of both the American military and its partners in their effort to destroy the Islamic State and its Syrian base.