Three Syrian tanks entered the demilitarised zone in the Golan Heights between Israel and Syria on Saturday, an Israeli military spokesperson said.
"The Israeli Defence Forces have filed a complaint with the UN (peacekeeping) force in the area," the spokesperson said.
She had no further information on what the tanks were doing. Israeli media said the tanks were involved in fighting rebels trying to overthrow Syrian President Bashar al-Assad. Israel captured the Golan Heights, a strategic plateau, from Syria during a 1967 Middle East war. The Golan demilitarised zone has been largely quiet since a 1973 ceasefire.