Sam Zell has put together a $625m fund to buy distressed securities backed by assets including commercial real estate.

The 67-year-old billionaire filed a private-placement notice last month for Zell Credit Opportunities Fund LP, described as a private-equity fund that received its initial backing from a pair of unidentified investors.

The fund represents Zell’s return to distressed investing. Investors expect trillions of dollars in maturing debt on commercial real estate to trigger a wave of bank foreclosures and loan sales.

The Zell fund 'is a harbinger of what is to come,' said John Goff, who co-founded Crescent Real Estate Equities Co. with billionaire Richard Rainwater. 'A lot of loans are coming due and there are going to be a whole host of opportunities.'