Open hostilities between Israel and Iran entered a fourth day on Monday with no sign of easing, stoking fears of a wider war in the oil-rich region.

It follows daytime attacks from both sides, with Israeli strikes in Tehran continuing and Iran firing more missiles towards Israel.

Ahead of Friday's attack on Iran, Israel had spent months smuggling in parts for hundreds of quadcopter drones rigged with explosives—as well as munitions that could be fired from unmanned platforms,