Here's what would happen in the first 72 hours of WW3

Fears of a Third World War have been rising ever since America and Israel launched joint attacks on Iran, killing Supreme Leader Ayatollah Ali Khamenei.

Following the strikes on Saturday (28 February), which US President Donald Trump said were to 'ensure that Iran does not obtain a nuclear weapon,' the Middle Eastern country retaliated with counter-attacks of its own.

Iran targeted American and Israeli assets and allies, specifically Bahrain, Kuwait, Qatar, Jordan, and the United Arab Emirates (UAE).

Now, on the fourth day of the conflict, Iran's death toll from US-Israeli strikes has climbed to 787, according to state media citing the Iranian Red Crescent.

With the growing number of casualties and other countries becoming affected, questions have arisen over whether the violence could explode into a full-scale World War.

From looking at where it is safest to be, to who would be drafted to the frontlines, and what you'd need to stockpile for an emergency kit, some people have been preparing for a worst-case scenario.

So, here's what might happen if WW3 were to break out.

Fears of a third World War are on the rise, amid the ongoing conflict in the Middle East (Contributor/Getty Images)

Survival kits would be utilised

Last March, people in the EU were advised by the European Commission to stockpile enough essentials that would last them for at least 72 hours.

This guidance was given as part of 'proactive measures to prepare for crises, such as developing household emergency plans and stockpiling essential supplies'.

However, it's important to remember that this advice came, as we say, last year, and wasn't given in response to the current conflict in the Middle East.

The essential items listed that you can put together in an emergency kit include:

• Bottled water and portable water filters
• Non-perishable food and energy bars
• Torches and backup batteries
• Fire-starting tools and a first-aid kit
• Warm clothing and shelter equipment
• Multi-tool or survival knife
• Communication devices such as radios
• Important identification documents and cash
• Navigation tools such as a compass and maps

Experts have warned that nuclear war would have catastrophic consequences (Getty Stock Image)

Nuclear war and high casualties

If a nuclear war broke out, the results would be catastrophic - experts believe that most of the Earth's population would be dead and the land would be scorched.

The International Campaign to Abolish Nuclear Weapons (ICAN) points out that a single nuclear bomb detonated over a large city could kill millions of people.

The use of tens or hundreds of nuclear bombs would disrupt the global climate, causing widespread famine.

Casualties from a major nuclear war between the US and Russia, for example, would reach hundreds of millions, causing devastating casualties.

In the long-term, nuclear weapons produce ionizing radiation, which kills or sickens those exposed to it, contaminates the environment, and has long-term health consequences, including cancer and genetic damage.

Bestselling author Annie Jacobsen, who wrote the book Nuclear War: A Scenario, said that around five billion people would be dead within the first 72 minutes.

Previously speaking on the Diary Of A CEO podcast, the expert predicted the initial damage would be followed by a mini-ice age.

She said: "Most of the world, certainly the mid-latitudes, would be covered in sheets of ice …places like Iowa and Ukraine would be just snow for 10 years.

"Agriculture would fail, and when agriculture fails, people just die. On top of that, you have the radiation poisoning because the ozone layer will be so damaged and destroyed that you couldn't be outside in the sunlight - people will be forced to live underground."

As we say, though, of course, isn't happening right now; it's simply a prediction of what could happen in a worst-case scenario, so don't panic yet.