LONDON — A fund linked to the private equity firm Carlyle Group became the latest investment firm to run into trouble amid deteriorating credit markets when it said on Thursday that it failed to meet some margin calls and had received a notice of default.

The Carlyle Capital Corporation, which is based in Guernsey, Channel Islands, and invests mainly in triple-A rated mortgage securities, missed four of seven margin calls worth a total of $37 million and said it expects to receive at least one more default notice as banks call in loans.

“As the market continues to go down it becomes ever more difficult to meet margin calls,” said Joseph A. Biernat, director of research at the fund manager, European Credit Management, in London. “Even if there is no risk for the securities, no one wants to support high levels of leverage these days.”