MADRID, Oct 22 (Reuters) - Spanish bank Santander

had debt exposure to bankrupt auto parts maker First

Brands Group of at least $55 million by the end of September, a

U.S. court document, seen by Reuters, showed.

The collapse of First Brands and subprime lender and

dealership Tricolor has unsettled Wall Street's

multitrillion-dollar credit market, which includes leveraged

loans, collateralised loan obligations, trade-finance funds and

subprime auto loans.

The U.S. court documents, filed in the U.S. bankruptcy court

for the southern district of Texas, also showed that the

Santander exposure is guaranteed by Bank of America ( BAC ).

Santander declined to comment on Wednesday on the U.S. court

document. Bank of America ( BAC ) was not immediately available for

comment.

The court documents showed that Santander had exposure to

First Brands of around $55 million through four transactions by

its subsidiaries in Mexico and Brazil - $32.55 million in the

Mexican subsidiary and $22.1 million in Santander Brazil.

Santander's exposure to First Brands was first reported

by Spanish newspaper Expansion.

The exposures were tied to entities of First Brands that

were not part of the U.S. business and not involved in the

Chapter 11 proceedings, a source familiar with matter said.

Separately, the Wall Street Journal has reported that when

First Brands filed for bankruptcy in September, it had a $77

million loan from Santander, also tied to a firm not part of

bankruptcy proceedings.

Santander declined to comment on the Wall Street Journal

report, which Reuters was not able to confirm.