BY CHAD BRAY AND LAURA SAUNDERS

U.S. prosecutors filed criminal charges against Switzerland's oldest bank, alleging it helped wealthy Americans hide more than $1.2 billion in secret accounts abroad, the latest move in an ongoing crackdown on overseas tax evasion.

The indictment of Swiss private bank Wegelin & Co., founded in 1741, marks the first time U.S. authorities have charged a bank rather than individuals with helping Americans evade taxes.

U.S. authorities said they also seized more than $16 million from an account Wegelin has with Swiss bank UBS AG in Stamford, Conn.

"Wegelin Bank aided and abetted U.S. taxpayers who were in flagrant violation of ...