An Israeli fighter jet has been shot down after it carried out a raid on Iranian targets in Syria.
The F-16 crashed in northern Israel after coming under anti-aircraft fire in its neighbouring country on Saturday.
Two pilots ejected from the plane before it crashed and were taken to hospital.
Israeli aircraft had been carrying out raids against Iranian targets in Syria after one of their drones entered Israeli airspace.
Israel described the Iranian drone's actions as a "severe violation of Israeli sovereignty", while Syrian state TV described the subsequent bombing run as an act of "aggression".
This is believed to be the first time an Israeli aircraft has been successfully shot down during the Syrian conflict.
Syrian state TV quoted a military official saying Syrian air defenses hit more than one Israeli plane.
In recent months Israel has warned of increased Iranian involvement along its border in Syria and Lebanon. It fears Iran could use Syrian territory to stage attacks or create a land corridor from Iran to Lebanon that could allow it to transfer weapons more easily to Hezbollah.
Israel has shot down several drones that previously tried to infiltrate its territory from Syria. The targeting of an Iranian site in response, however, marks an escalation in the Israeli retaliation.
Israel's chief military spokesman said Israel held Iran directly responsible for the incident.
"This is a serious Iranian attack on Israeli territory," Brigadier General Ronen Manelis said.
"Iran is dragging the region into an adventure in which it doesn't know how it will end. Whoever is responsible for this incident is the one who will pay the price."