The Israeli military says a missile was fired into Israel from neighbouring Syria early on Thursday, and Israel has retaliated by striking targets in the neighbouring territory.
Sirens have sounded in the southern Israeli district of Abu Qrenat near the Dimona nuclear reactor, the Israeli Defence Force said without immediately providing further details.
Sirens indicate a possible attack on the sensitive area.
The Israeli military said the missile landed in the Negev region, though it did not say whether anything was struck.
Israeli media also reported loud explosions in central Israel.
A Reuters reporter about 90 kilometres away from Abu Qrenat heard the sound of an explosion minutes before the military’s text message.
Israel’s Army Radio said that, if such an attack had taken place early on Thursday, its origin was not immediately clear.
Abu Qrenat is deeper within Israeli territory than the usual range of the rockets of Palestinian militants in the Gaza Strip.
Israeli media have said for weeks that air defences in the area of Dimona and the Red Sea port Eilat were being beefed up in anticipation of a possible long-range missile or drone attack by Iranian-backed forces — perhaps from as far away as Yemen.
Syria’s state news agency said the country’s air defences intercepted an Israeli attack in the direction of the Golan Heights on Thursday.
The attack took place at around 1:38am local time and targeted areas in the Damascus suburbs, the agency said.
“Air defences intercepted the rockets and downed most of them,” it said.
The reports came amid heightened tensions between Israel and its archenemy Iran.
Iran, which maintains troops and proxies in Syria, has accused Israel of a series of attacks on its nuclear facilities, including sabotage at its Natanz nuclear facility on April 11, and vowed revenge.
It also threatened to complicate US-led attempts to revive the international nuclear deal with Iran.
Iran recently began enriching a small amount of uranium up to 60 per cent purity, the highest level ever for its program that edges even closer to weapons-grade levels. However, Iran insists its program is for peaceful purposes.
Israeli Prime Minister Benjamin Netanyahu has repeatedly said Israel will not allow Iran to develop a nuclear weapons capability, and defence officials have acknowledged preparing possible attack missions on Iranian targets.
All the incidents come as Iran negotiates in Vienna with world powers over the US potentially re-entering its tattered nuclear deal with world powers