DAMASCUS - Explosions were heard in several cities in Syria early on Sunday, as tensions escalated between Iran and Israel, according to reports by a war monitor.

Explosions were heard in the Syrian capital of Damascus, as well as Homs, Hama, Daraa, and coastal regions, as Syrian air defenses attempted to intercept Israeli missiles that were allegedly targeting Iranian missiles en route to hit targets in Israel, according to the Syrian Observatory for Human Rights.

Israeli aircraft reportedly intensified surveillance over western Daraa countryside and Quneitra, the UK-based watchdog group added.

Sounds of explosions filled the air, but there have been no reports any Syrian targets were actually hit.

Iran announced earlier it launched missile and drone attacks on Israel, in retaliation to an Israeli missile attack on the Iranian consulate in Damascus on April 1.