Israel scrambled jets to its northern border with Syria on Friday, after Syrian fighter planes and a helicopter were spotted in the area.

The Syrian aircraft were apparently firing on rebel positions near the border, according to Channel 2 News. They came within a few hundred meters of the Israeli border, the TV report said.

Syria’s planes pulled back after spotting the Israelis, reported Haaretz.

There was no direct contact between the two countries’ aircraft.

An Israeli military source said that Syrian activity in the area was not uncommon, but that an alert was raised when multiple planes were detected within a few hours, according to the report. It is very rare for Israel to scramble its jets in this way.

Channel 2 reported that Syrian planes have operated close to the border in the past, during the civil war, but that Syria has warned Israel in advance via the UN that they would be operating in the area. On this occasion, there was no such advance warning.

Assad says his troops are fighting Islamic extremists who want to destroy Syria. The now 3-year-old conflict — that started as a largely peaceful uprising against the Syrian president’s rule but turned into a civil war — has claimed at least 140,000 lives.

On Wednesday, IDF forces spotted two terrorists trying to plant explosives on the Israel-Syria border in the northern Golan Heights, according to the IDF Spokesperson’s office.

Soldiers opened fire at the suspects, and identified direct hits. The men belonged to an organization affiliated with the Lebanese Shi’ite terrorist group Hezbollah, the IDF said.