Michael Cohen has never faced attorneys like the ones investigating him.

The federal prosecutors looking into Cohen, the longtime lawyer and fixer for Donald Trump, have deep and varied experience with financial crimes such as bank fraud, money laundering, and racketeering. On Friday, they submitted a court filing that gave the first glimpse into the investigation that exploded into the public eye with an FBI raid on Cohen’s office and home on Monday.

“The searches are the result of a months-long investigation into Cohen,” according to the filing submitted by the U.S. Attorney’s Office for the Southern District of New York, into acts of concealment and fraud he may have committed. While prosecutors did not disclose those acts, the search warrant served on Cohen reportedly sought documents pertaining to his efforts to pay off two women during the 2016 presidential campaign who said they had sex with Trump, among other topics.

Cohen claims he paid $130,000 of his own money to Stephanie Clifford, aka porn star Stormy Daniels, in October 2016. In exchange for the money, Clifford signed a nondisclosure agreement stipulating she would not discuss her alleged affair with Trump. Cohen set up a shell company that obscured the payment and the agreement. The other woman, Karen McDougal, claims in a lawsuit that Cohen was secretly involved in her talks with the National Enquirer’s publisher to “catch and kill” her story on Trump.

“ The prosecutors have deep and varied experience with financial crimes such as bank fraud, money laundering, and racketeering. ”

Shady financial dealings are what Thomas McKay, Rachel Maimin, and Nicolas Roos are used to digging into. They are the assistant U.S. attorneys who wrote the court filing Friday in response to Cohen’s motion to a federal judge to keep records seized by the FBI out of prosecutors’ hands.

McKay and Roos are part of the public corruption unit of the U.S. Attorney’s Office for the Southern District of New York, which goes after corruption crimes committed by government officials, as well as frauds committed against the government.

McKay was part of the team that convicted New York’s former Senate majority leader, Dean Skelos, for crimes including using his office to pressure businesses to give his son hundreds of thousands of dollars. The 2015 conviction was overturned by an appeals court thanks to a 2016 Supreme Court decision that narrowed the definition of corruption; a retrial is scheduled for later this year.

Roos recently charged an NYPD detective with bank fraud for stealing $1.5 million from victims by depositing the money into accounts the cop controlled. A month earlier, he charged a graduate school employee and students with conspiracy to commit wire fraud by creating a kickback scheme to pocket financial aid. Last year, he prosecuted an international money laundering scheme to bribe African officials and another plan to con financial institutions and investors into giving loans to phony businesses.

Maimin comes from the violent and organized crime section of the attorney’s office, which has seen her prosecute multiple cases of racketeering, including the largest gang takedown in New York history that saw 120 members and associates of two rival Bronx street gangs charged in 2016.