A missile launched from Syria was fired into southern Israel early Thursday, setting off air raid sirens near the Shimon Peres Negev Nuclear Research Center in the southern town of Dimona, the Israeli military said. In response, it said it attacked the missile launcher and air-defense systems in neighboring Syria.

The incident, marking the most serious violence between Israel and Syria in years, pointed to likely Iranian involvement. 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.

The Israeli military said it had deployed a missile-defense system but could not confirm if the incoming missile was intercepted, though it said there had been no damage. The air raid sirens were sounded in Abu Krinat, a village just a few kilometers from Dimona, the desert town which, according to foreign reports, houses the country’s undeclared atomic weapons program. Explosions heard as far away as Jerusalem and the Shfela District area might have been the air-defense systems.

The Israel Defense Forces initially described the weapon fired as a surface-to-air missile, which is usually used for air defense against warplanes or other missiles, that it said had been fired at Israeli aircraft during an earlier strike and had overflown its target and reached the Dimona area.

The errant Syrian missile was an SA-5, one of several fired at Israeli Air Force planes, according to the spokesman.

However, Dimona is some 300 kilometers (185 miles) south of Damascus, a long range for an errantly fired surface-to-air missile.

The IDF said that in response to the launch, it attacked several missile batteries in Syria, including the one that fired the projectile that struck its territory.

Syria’s state-run SANA news agency said four soldiers had been wounded in an Israeli strike near Damascus, which also caused some damage. The agency did not elaborate other than to claim its air defense intercepted “most of the enemy missiles,” which it said were fired from the Israeli Golan Heights.

A Syrian military defector said the Israeli strikes targeted locations near the town of Dumair, some 40 km northeast of Damascus, where Iranian-backed militias have a presence. It is an area that Israel has hit repeatedly in past attacks

There was no immediate claim of responsibility for the missile strike or comment from Iran. But on Saturday, Iran’s hardline Kayhan newspaper published an opinion piece by Iranian analyst Sadollah Zarei suggesting Israel’s Dimona facility be targeted after the attack on Natanz. Zarei cited the idea of “an eye for an eye” in his remarks.

Action should be taken “against the nuclear facility in Dimona,” he wrote. “This is because no other action is at the same level as the Natanz incident.”

Israeli media have said for weeks that air defenses around the Dimona facility 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.

While Kayhan is a small circulation newspaper, its editor-in-chief, Hossein Shariatmadari, was appointed by Supreme Leader Ayatollah Ali Khamenei and has been described as an adviser to him in the past.

Zarei has demanded retaliatory strikes on Israel in the past. In November, he suggested Iran strike the Israeli port city of Haifa over Israel’s suspected involvement in the killing of a scientist who founded Iran’s military nuclear program decades earlier. However, Iran did not retaliate then.

All the incidents come as Iran negotiates in Vienna with world powers