The Americans have been keen say their attack on Iranian weapons and ammunition facilities were not directly linked with the situation in Israel and Gaza, ITV News' Emma Murphy and Robert Moore report
The situation in the Middle East has suddenly become still more perilous.
In parallel to the Israel-Hamas war, two other powerful adversaries - the United States and Iran - are now edging closer to a full military confrontation.
Last night, US F-16 fighter-jets bombed Iranian targets in eastern Syria.
It follows Iranian-backed proxies launching rocket and drone attacks on American bases in Iraq and Syria, injuring a number of US troops.
American defence officials say their attack on Iranian weapons and ammunition facilities overnight was a carefully calibrated warning to Tehran. They also insist it is quite separate from the Israel-Gaza crisis.
ITV News Correspondent Robert Moore reports live from Washington
But everything is connected and America’s posture in the region has suddenly lurched from the diplomatic to the military.
There are two carrier battle groups in the eastern Mediterranean, and US reinforcements and anti-missile batteries are being sent to the region.
There is a fear that Hezbollah may soon launch a sustained rocket attack on Israel, possibly overwhelming the Iron Dome anti-missile defence shield.
The key question is what Tehran will do in response to the overnight American precision strikes.
Will they seek to bait President Biden into a major military confrontation, believing that it would do the US untold diplomatic damage in the region? Or does Tehran fear that an Israeli-US military axis will simultaneously attack Hamas, Hezbollah, and multiple other proxies and seek to crush Iranian influence?
We are about to find out. These are exceptionally dangerous days, with the greatest risk of escalation since the Six Day War of 1967.
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