"We are incredibly saddened by the tragic loss of our colleague," Perella said in a statement, without giving details.

German authorities said last week they were investigating five suspects for allegedly profiting to the tune of millions of euros on upcoming M&A transactions between 2017 and 2021.

One of the suspects was a Perella employee in London who had been placed on leave, Reuters and media outlets reported at the time.

Perella said on Tuesday it was assisting in a German investigation and that "the firm is not the subject of any investigation".

The investment bank advised in some of the largest European deals last year, such as Siemens Energy's takeover offer for Siemens Gamesa and DigitalBridge on its acquisition of a 51% stake in Deutsche Telekom's German and Austrian tower business in consortium with Brookfield. 

British police also searched Perella's office last week as part of the investigation, Reuters and other media have reported.

A spokesperson for Frankfurt's prosecutors didn't immediately respond to a request for comment outside of business hours on Tuesday.

The prosecutors and Germany's financial regulator BaFin have said they had been conducting their investigation since November 2021 before carrying out searches this month in Germany, Britain and Austria. They are now evaluating evidence that was seized.

Authorities described profits from the alleged trades as a two-digit million euro figure. The transactions involved German companies and all of the suspects are German nationals. One has been in custody.

Bloomberg first reported news of the death.

(Reporting by Tom Sims and Andres Gonzalez Estebaran; Editing by Mark Potter)