JERUSALEM (Reuters) - The Israeli air force attacked a Syrian anti-aircraft battery on Monday that Israel said had fired a missile at its planes while they were on a reconnaissance mission over neighboring Lebanon.

No Israeli planes were hit, Israeli military spokesman Lieutenant-Colonel Jonathan Conricus said. The counter-strike took place two hours later and “incapacitated” the anti-aircraft unit located 50 km (30 miles) east of Damascus, he said.

“We know according to our intelligence it was a battery controlled by the Syrian regime and we hold the Syrian regime responsible for the fire,” Conricus said.

Prime Minister Benjamin Netanyahu later issued a statement saying Israel would not hesitate to defend itself.

“Today there was an attempt to harm our aircraft -- this is unacceptable to us. The air force acted quickly and accurately to destroy what needed to be destroyed,” Netanyahu said.

“Our policy is clear. Whoever tries to harm us, we will strike at him. We will continue to act in the region as is required in order to defend Israel.”

But the Syrian army said it struck an Israeli warplane that had breached its air space at the Syria-Lebanon border.

“The Israeli enemy this morning violated our air space... Our air defense mediums confronted it, hit one of its planes directly and forced it to flee,” the Syrian military statement said.

“GRAVE CONSEQUENCES”

Over two hours later, Israel launched several missiles that hit a military position in the Damascus countryside and only caused material damage, it said. Syria’s army warned Israel against the “grave consequences of repeated aggressive attempts”.

Syria and Israel, while old enemies, have rarely traded blows directly since a 1974 ceasefire ended their last conventional war.

Monday’s incident was additionally unusual given its publication by Israel, which rarely gives details on its air force activities over Lebanon and Syria to foil suspected arms transfers to Iran-backed Hezbollah fighters.

Such missions in Syria have increased dramatically during the country’s six-and-a-half-year-old civil war, Israeli officials say. All efforts, they say, are made to avoid accidental clashes with Russian forces helping Damascus beat back insurgents.

Russian Defence Minister Sergei Shoigu began a visit to Israel later on Monday but did not mention the air strike during public remarks at the start of a meeting in Tel Aviv with his Israeli counterpart, Avigdor Lieberman.

“I would like to talk about the things related to Syria. The operation there is close to the end. There are several problems which require urgent solution and the prospects of further development of the situation in Syria require discussion,” Shoigu said.

Conricus said the Israeli military had informed Russia of its Syria strike “in real time or immediately before” it took place, and would brief Shoigu.

The Lebanese army says Israeli aircraft regularly violate Lebanon’s air space.

Conricus said a Syrian attack on Israeli air force planes over Lebanon was unprecedented. Syrian anti-aircraft missiles were launched at Israeli warplanes over Syria in March. They were unscathed but one of the missiles, on its descent, was intercepted by Israel’s Arrow air defense system.

According to Conricus, the Syrian battery struck on Monday had carried out the launch against the Israeli planes in March.