Why did the FBI search Mar-a-Lago and what was found?

FBI agents, top secret documents and a former president's sprawling beachside estate.

When Donald Trump's Florida home was searched by government agents earlier this week, it unleashed a political firestorm unlike anything in recent memory.

This unprecedented story is complicated and many questions still remain. So let's take a step back - here's what we know so far.

Why did the FBI search Mar-a-Lago?

In short, because the US Department of Justice suspects the former president may have committed a crime.

The search warrant, which has been made publicly available, shows FBI agents gathered evidence on 8 August as part of an investigation into whether Mr Trump mishandled government records by taking them from the White House to Mar-a-Lago.

It's worth noting here that US presidents must transfer all of their documents and emails to a government agency called the National Archives.

Earlier this year, that agency said it had retrieved 15 boxes of papers from Mar-a-Lago which Mr Trump should have handed over when he left the White House. It said they included classified information and asked the justice department to investigate.

To obtain the search warrant, prosecutors had to persuade a judge that they had probable cause to believe a crime may have been committed. We also know that the effort to seek a search warrant was signed off by the head of the justice department - the attorney general - who is the country's top legal official.

What did the agents take?

Twenty boxes worth of material, according to an inventory released alongside the search warrant on Friday.

The FBI took 11 sets of classified files in total, including four that were labelled "top secret". Three sets were classified as "secret documents" and three were "confidential".

The cache also included files marked "TS/SCI", a designation for the country's most important secrets that if revealed publicly could cause "exceptionally grave" damage to US national security.