Donald Trump, the ex-president and frontrunner to be Republican nominee in 2024, is set to face a mug shot, finger-printing and a court appearance next week after being indicted over a probe into hush money paid to a porn star in an historic U.S. first.

The possible spectacle of Trump's appearance in Manhattan before a judge with media camped outside could further divide the world's most powerful country.

The specific charges against Trump are not yet known as the indictment remains under seal, but CNN on Thursday reported Trump faced more than 30 counts related to business fraud.

Trump, 76, said he was "completely innocent" and accused Manhattan District Attorney Alvin Bragg, the Democrat who led the investigation, of trying to hurt his electoral chances.

"This is Political Persecution and Election Interference at the highest level in history," Trump said in a statement.

Shortly after, Trump appealed to supporters to provide money for a legal defense.

He has raised over $2 million since March 18, according to his campaign, and called for people to protest.

A small number of supporters rallied at Trump's Mar-a-Lago property in Florida on Thursday, waving flags along the highway, while a critic of the former president held a sign near the New York DA's office reading: "Lock him up and throw away the key".

Authorities bolstered security around the Manhattan courthouse after Trump earlier this month called for nationwide protests, recalling his charged rhetoric ahead of the Jan. 6, 2021, attack on the U.S. Capitol by his supporters.

Neither the White House nor President Joe Biden, a Democrat who is widely expected to seek re-election in a possible rematch against Trump, commented on Thursday.

But the party's top senator, Majority Leader Chuck Schumer, called for matters to play out calmly.

"I encourage both Mr. Trump's critics and supporters to let the process proceed peacefully and according to the law," he said in a statement.

LEGAL BATTLES

The Manhattan investigation is just one of several legal challenges concerning Trump.

Trump also faces a separate criminal probe into whether he unlawfully tried to overturn his 2020 election defeat in Georgia, and two investigations by a special counsel including over his handling of classified documents after leaving office.

The Manhattan charges will likely be unsealed by a judge in the coming days and Trump will have to travel there for fingerprinting and other processing at that point.

He is expected to appear before a judge next week where the charges will be formally read, according to a court official.

Trump's lawyers Susan Necheles and Joseph Tacopina said they will "vigorously fight" the charges.

Trump received support from a number of his potential challengers for the Republican nomination on Thursday including Florida Governor Ron Desantis and former Vice President Mike Pence.

"This will only further serve to divide our country," Pence said.

Trump could use the case to stoke anger among his core supporters, though other Republican voters might tire of the drama.

Some 44% of Republicans said he should drop out of the race if he is indicted, according to a Reuters/Ipsos poll released last week.

AFFAIRS ALLEGED

While president between 2017 and 2021, Trump regularly butted heads and used fiery rhetoric with traditional American allies in the West over matters such as trade and defense spending.

Trump's style has been emulated by other world leaders, and he has been critical of U.S. support for Ukraine following Russia's invasion.

Trump has escaped legal peril numerous times.

In the White House, he weathered two attempts by Congress to remove him from office, over the U.S. Capitol assault by supporters and probe into his campaign's contacts with Russia in 2016.

The Manhattan District Attorney's office successfully prosecuted Trump's business on tax-fraud charges last year, leading to a $1.61 million criminal penalty.

The presiding judge in that case, New York Supreme Court Justice Juan Merchan, is expected to oversee the Daniels case as well, according to a person familiar with the matter.

Legal experts say Bragg is expected to argue Trump falsified business records to cover up another crime, such as violating federal campaign-finance law, which makes it a felony.

Daniels, whose real name is Stephanie Clifford, has said she received money in exchange for keeping silent about a sexual encounter she had with Trump in 2006.

The former president's personal lawyer Michael Cohen has said he coordinated with Trump on the payments to Daniels and to a second woman, former Playboy model Karen McDougal, who also said she had a sexual relationship with him.

Trump has denied having affairs with either woman.

Trump in 2018 initially disputed knowing anything about the payment to Daniels. He later acknowledged reimbursing Cohen for the payment, which he called a "simple private transaction."

"No one is above the law," Daniels' lawyer Clark Brewster said on Twitter.

Cohen pleaded guilty to a campaign-finance violation in 2018 and served more than a year in prison. Federal prosecutors said he acted at Trump's direction.

Cohen said he stood by his testimony and the evidence he provided to prosecutors.

"Accountability matters," he said in a statement.