What is Russia's ship-killing missile and why does it scare navies around the world?
The P-800 Oniks is one of Russia's most powerful supersonic anti-ship cruise missiles.
It is guided by satellite and can be launched from land or sea.
And with its supersonic speed and sea-skimming trajectory, it has good odds of avoiding naval defence systems and defeating electronic countermeasures.
The Oniks, which has the Nato codename SS-N-26 Strobile, can carry a conventional or nuclear payload.
And while the latter makes it capable of destroying a target such as an aircraft carrier, its conventional warhead can inflict a devastating amount of damage too.
The missile entered service in 2002 and is operated by countries such as Syria in addition to Russia.
However, the thought of a terrorist group aligned with a Russian ally getting hold of the missile is what most scares the Western naval vessels that are responding to the current crisis in the Middle East.