JERUSA LEM: Israel said its warplanes carried out a `very intense` attack against Iranian forces and Syrian army targets in Syria on Wednesday, in raids a monitoring group reported killed at least 23 people.

In a rare confirmation of their operations in Syria, the Israeli army said they had carried out dozens of strikes against the Iranian elite Quds Force and the Syrian military, in response to four rockets reportedly fired at Israel a day before.

Britain-based monitoring group the Syrian Observatory for Human Rights (SOHR) said 23 people were killed in the strikes 21 fighters and two civilians.

Sixteen were non-Syrian fighters, the group`s head Rami Abdel Rahman said.

Iran has fought alongside Syrian President Bashar alAssad`s forces in the country`s eight-year civil war, heightening Israeli concerns over the presence of its archenemy along its border.

`This is what we did overnight vis-a-vis military targets of the Iranian Quds Force and Syrian military targets in Syria after a barrageofrocketswaslaunched at Israel,` said Israeli Prime Minister Benjamin Netanyahu in a statement.

The Israeli army said they had targeted about a dozen military sites, including warehouses and military command centres.

`It was very intense, spokesman Jonathan Conricus said. The most important target, he said, was a control facility at the main international airport in Damascus.

`It is the main building that serves the (Iranian) Revolutionary Guards... for coordinating the logistic facilities of transport of military hardware from Iran to Syria and from Syria onwards,` he said.

Israel has carried out frequent air and missile strikes against Iranian targets inside Syria since the country descended into civil war in 2011, but rarely comments on them.

On Tuesday, four rockets were fired at Israel from Syria, with the army blaming an `Iranian force`.

Israel`s Iron Dome missile defence system intercepted the rockets.

Conricus alleged it was the sixth time Iranian forces had tried to attack Israel directly in recent years, most recently in August.

The Israeli attack on Wednesday began in the early hours, with a series of large explosions rocking Damascus, a correspondent in the city said.

Syria`s state news agency SANA said Syrian anti-aircraft defences responded to a `heavy attack` by Israeli warplanes over the capital.

The Israeli army confirmed missiles were fired towards its jets but denied any were hit.

In response to the fire, it said, `a number of Syrian aerial defence batteries were destroyed`.

SANA added that the strikes were carried out from `Lebanese and Palestinian territories`.

Israel sometimes launches attacks on Syria from planes flying over neighbouring Lebanon.-AFP