Continental Illinois will buy 3 suburban banks.

The Chicago bank said it has won federal approval to buy three suburban banks in deals that were opposed by some smaller Illinois banks. The Federal Reserve Board approved Continental’s applications to buy First National Bank of Deerfield, First Suburban Bank of Olympia Fields and First National Bank of Western Springs, a Continental spokesman said. Smaller Illinois banks opposed the purchases because Continental had been rescued in 1984 by a federal bailout using funds from other banks.