New York state attorney general Elliot Spitzer, fresh from doing battle with Wall Street giant Merrill Lynch, has sued a marketing firm which allegedly sent millions of unsolicited e-mail advertisements.

Mr Spitzer's lawsuit against Niagara Falls-based MonsterHut.com accuses it of falsely telling clients that it sent the e-mails with consumers' consent.

Under New York state's advertising laws, the company could be ordered to pay a $500 (£342; 538 euros) penalty for each unsolicited message.

Mr Spitzer's lawsuit stated that more than 750,000 consumers asked to be removed from MonsterHut's mailing list, while others complained directly to MonsterHut's internet service provider.

"Negative consumer response to MonsterHut's spam has been overwhelming," the lawsuit said.

Growing problem

Mr Spitzer is also hoping to force the company to reveal how it obtained the e-mail addresses of the consumers on its mailing list.

Spam mail, often offering to sell the recipient services such as holidays, weight-loss techniques, or access to pornography, can clog up and slow down computer networks.

Internet service providers such as AOL have successfully sued "spammers" using trespass or computer fraud legislation.

In the US, 19 states including New York have introduced specific anti-spam regulations.

Merrill battle

Mr Spitzer, New York state's chief prosecutor, earlier this year launched legal action against Wall Street brokerage Merrill Lynch for allegedly giving misleading investment advice to clients.

The move stemmed from allegations that Merrill analysts tipped stocks they privately disparaged so as to keep open the possibility of gaining investment banking business from the companies concerned.

Earlier this month, Merrill Lynch paid a $100m penalty and issued a public apology to settle the lawsuit.