The FBI raided the office and hotel room of President Donald Trump’s personal lawyer on Monday as part of a fraud and campaign finance investigation. Hours later, Trump called the raid an “attack on our country” and speculated that “we’ll see what happens” when asked if he planned to fire special counsel Robert Mueller.

Significantly, Mueller’s probe has also turned its sights on a $150,000 donation from a Ukrainian billionaire made to Trump’s charity, which previously admitted it violated tax law and helped Trump personally, during the campaign.

All of a sudden, Mueller’s Russia investigation is red-hot, and it’s getting much closer to the president. Here’s what you need to know about the past 24 hours of news in Mueller’s investigation into the Trump-Russia scandal.

Mueller’s investigation has been looking into Trump’s longtime lawyer Michael Cohen, although the US attorney’s office for the Southern District of New York carried out the raid. Bloomberg reported that Mueller uncovered potential crimes by Cohen during his Russia investigation, and brought the findings to Deputy Attorney General Rod Rosenstein. Rosenstein decided to send the case to the New York office, which led the search of Cohen’s office and hotel (his home is undergoing renovation).

Under the law, Mueller has to tell Rosenstein about any crimes he uncovers that aren’t directly under the mandate of his investigation. It is then up to Rosenstein decide whether another prosecutor should go after the charges.

The raid brings the case closer to Trump’s door than any to date, touching a close Trump confidant — and potentially a speech made by Trump himself. Trump wasn’t pleased and made aggressive comments to the press on Monday evening, right as news broke that Mueller’s team is looking at a donation to Trump’s charity tied to a speech Trump gave during the campaign.

The past 24 hours in the Mueller investigation, explained

Cohen is the man in the middle of the controversy over Stormy Daniels. Daniels, a porn actress, says she had an affair with Trump in 2006. Cohen paid her $130,000 days before the 2016 presidential election in exchange for her keeping quiet about the relationship.

The investigation into Cohen is tied to that payment, with legal experts saying he may have violated campaign finance law. If Cohen used the money to keep the affair secret and help Trump win the election, the payoff could be considered a donation — one that violates campaign finance law. Cohen could have been trying to help by keeping an embarrassing story from the press. If that’s the case, the donation was never properly reported to the federal government, and it would substantially exceed the legal cap on donations.

The FBI is also looking at whether Cohen violated any banking or wire transfer laws by using a personal bank loan to pay off Daniels, whose legal name is Stephanie Clifford.

Cohen’s lawyer, Stephen Ryan, said that the raid was “completely inappropriate and unnecessary” and pointed out that attorney-client privilege may shield many of Cohen’s files from investigators, a legal concept that protects communication between lawyers and their clients.

But the privilege doesn’t apply if the lawyer is committing a crime.

Although it isn’t Mueller’s team that led the search, Trump is directly blaming Mueller, according to the New York Times. The president responded to the raids with some of his most heated criticism of Mueller and his investigation to date.

Trump explodes at Mueller

Trump was about to hold a meeting with military leaders at the White House Monday to discuss the situation in Syria when he fielded a string of questions from reporters about the probe and attacked Mueller.

“It’s a real disgrace. It’s an attack on our country in a true sense,” Trump said. “It’s an attack on what we all stand for, so when I saw this and when I heard it, I heard it like you did, I said that is really now in a whole new level of unfairness.”

Trump repeated his claim that the investigation is a “witch hunt” and declined to answer whether he would now fire Mueller.

“We’ll see what happens,” Trump said. “I think it’s disgraceful, and so do a lot of other people.”

Trump has toyed with firing Mueller before, but several factors make that a difficult choice, including that Mueller’s investigation could go on without him, and it would likely be politically disastrous.

But Mueller just helped build a case against Cohen, and he’s digging into Trump’s personal activities, including a speech paid for by a Ukrainian billionaire.

Mueller is investigating the payment for a speech Trump gave during the campaign

One critical question that the Mueller probe has been looking at is whether foreign money flowed into Trump’s campaign during the 2016 election.

That has led Mueller’s team to a speech Trump delivered in September 2016 to a conference in Kiev, Ukraine. Trump filmed a speech and sent a video to the conference, and in exchange, a Ukrainian steel magnate donated $150,000 to Trump’s personal charity, the New York Times reported.

Cohen reportedly solicited the donation for Trump, although it is not related to Monday’s raids.

Trump’s charity, the Donald J. Trump Foundation, faced intense scrutiny during the election for spending money on items like a $20,000 portrait of Trump. After the election, the charity admitted that it violated tax law by helping Trump personally.

The focus on the speech and the donation is part of Mueller’s growing interest in overseas money and the Trump campaign. Much of Mueller’s case against Paul Manafort is tied to Manafort’s work in Ukraine, and Mueller’s team subpoenaed Trump’s businesses in March looking at Trump’s overseas deals.

The payment for a Trump speech brings the investigation to Trump personally. And the focus on Trump’s businesses and business colleagues may have violated Trump’s previous assertions that Mueller shouldn’t look into his companies. Trump’s non-answer as to Mueller’s future on Monday might be a sign that Mueller has to work quickly if he wants to finish his investigation before losing his job.