(Reuters) -U.S. auto parts maker First Brands filed for Chapter 11 bankruptcy protection on Monday, burdened by heavy debt from a flurry of acquisitions and stressed finances.

First Brands has obtained $1.1 billion in debtor-in-possession financing from its first-lien lenders to support ongoing operations, it said in a statement.

The company said that its Chapter 11 cases pertain solely to U.S. operations, and expects its global operations to continue uninterrupted.

Financial troubles at the auto parts supplier, coupled with the recent bankruptcy of subprime auto lender Tricolor Holdings, have rattled debt investors and stoked fears of broader stress in credit markets, according to bondholders and bankruptcy experts.

Bankers and creditors had been racing to restructure First Brands' $6 billion in debt as investor confidence eroded leading up to the filing, with several of its associated companies also declaring bankruptcy.

Privately-held First Brands makes replacement components including filters, brakes and lighting systems for the automotive aftermarket, and emerged as a significant player through debt-financed acquisitions of rival auto parts makers.

Its well-known brands include Raybestos brake solutions, TRICO wiper blades, and FRAM filtration products.

First Brands, which filed for bankruptcy in the Southern District of Texas, disclosed assets exceeding $1 billion against more than $10 billion in liabilities.

Last week, ratings agency Fitch downgraded First Brands' credit rating, saying the company's options for managing its debt were increasingly limited to off-market solutions.

Over the past week, First Brands' loans plummeted in value as its bondholders braced for the group's debt to be restructured.

Several Wall Street lenders and hedge funds, including Jefferies and Millennium, are exposed to First Brands' supplier invoice-linked facilities.

More than a dozen companies affiliated with First Brands Group, including Carnaby Capital Holdings, filed for bankruptcy protection last week, according to court documents signed by First Brands' owner and CEO Patrick James.

The affiliated entities had secured loans that were backed by guarantees from First Brands, a person familiar with the matter told Reuters.

Carnaby Capital Holdings' petition listed assets of over $500 million and liabilities exceeding $1 billion.

In addition to its debt, the company has several billion dollars more in financing facilities that are tied to its customers and suppliers, according to a source.

(Reporting by Shivansh Tiwary and Shivani Tanna in Bengaluru; Editing by Sriraj Kalluvila and Mrigank Dhaniwala)