New York Attorney General Andrew Cuomo says he's issuing subpoenas to more than 100 investment firms and their agents in his probe of an influence-peddling scandal affecting some of the nation's biggest public pension funds.

The investigation now touching on several states will look at individuals and companies who make or receive improper payments during lucrative business dealings with state and city pension funds.

State and federal law requires most securities brokers to be licensed, but Cuomo is looking to see how many unlicensed agents may be involved in pension investment deals.

Five people have been charged in a two-year probe led by Cuomo into allegations that investment companies paid millions of dollars in kickbacks to political figures to get pension fund business.