By Barbara Surk, Associated Press

BEIRUT (AP) — Three Syrian tanks entered the demilitarized zone in the Golan Heights on Saturday, Israel said, raising concerns violence from Syria's civil war could heat up a long-quiet frontier that has not seen such an incursion in nearly 40 years.

Three Syrian tanks entered on Saturday the demilitarized Golan Heights zone that separates Syria and Israel, prompting the Jewish state to lodge a complaint with United Nations monitors. [AFP]

Israel complained to U.N. peacekeepers present in the area, a relatively low-key response that suggested it did not see the Syrian armor as an immediate threat. But the entry marks the most serious spillover of Syria's turmoil to date at the frontier, where stray ordnance has exploded on the Israeli side in the past.

See what variety of incidents linked to the conflict other neighboring countries are dealing with;