Syria's state news agency SANA said its air defence systems downed several missiles launched from Israeli warplanes.

The Observatory said missiles struck Wadi al-Oyoun in the central province of Hama, near a scientific research centre which was already targeted by Israeli strikes in July and last year.

Iranian military positions in coastal region of Banias, in the province of Tartus, were also targeted, the Britain-based monitoring organisation said.

"There was material damage," said Observatory chief Rami Abdel Rahman.

"The air defence system responded to an Israeli aggression carried out by aircraft... that targeted some of our military positions in the provinces of Tartus and Hama," SANA said, quoting a military source.

"Some of the missiles" were downed, the agency said, reporting an initial casualty toll of one dead and four wounded.